by The long-running Sgt. Frog franchise is entering a major new chapter, and the upcoming TV anime Keroro Gunso☆ has officially revealed its new voice cast.
The completely new TV anime will premiere in Japan on October 3, 2026, airing every Saturday at 9:30 a.m. JST across six TV Tokyo network stations. It will be the first completely new Sgt. Frog TV anime series in approximately 15 and a half years, following the end of the previous television series in March 2011.
The biggest change is that the five members of the Keroro Platoon will all have new voice actors. Makoto Koichi will voice Keroro, Rika Nagae will play Tamama, Toshiki Masuda will voice Giroro, Kosuke Echigoya will play Kururu, and Keishi Inomata will take over as Dororo.
The announcement has understandably attracted significant attention from longtime fans, particularly because the previous cast had been associated with these characters for around two decades.
Interestingly, the new actors themselves have acknowledged that the change may be emotional for existing fans. Rather than ignoring the history of the franchise, the new cast members have repeatedly emphasized their respect and gratitude for the performers who came before them.
A New Sgt. Frog TV Anime Begins October 3
The new series, officially titled Keroro Gunso☆, will begin broadcasting on October 3, 2026.
The anime will air every Saturday at 9:30 a.m. on the TV Tokyo network, with broadcasts planned across six stations.
The upcoming production is being presented as a completely new TV anime, rather than a continuation of the previous television series. The production team has described the new anime as a fresh animation project, which is also the reason behind the decision to introduce a new voice cast for the main Keroro Platoon.
The first main promotional video and key visual were released on September 7, giving fans their first substantial look at the new version of Keroro, Tamama, Giroro, Kururu, and Dororo.
The promotional video also allows viewers to hear the new actors in character for the first time.
The Five-Member Keroro Platoon Has a Completely New Cast
The new voice cast for the central five-member squad is:
- Makoto Koichi as Sergeant Keroro
- Rika Nagae as Private Tamama
- Toshiki Masuda as Corporal Giroro
- Kosuke Echigoya as Staff Sergeant Kururu
- Keishi Inomata as Corporal Dororo
These five actors will be responsible for giving new voices to some of the most recognizable characters in the franchise.
For longtime viewers, this is likely to be one of the biggest adjustments when watching the new anime.
Keroro, Tamama, Giroro, Kururu, and Dororo have had the same Japanese voice actors for many years, making their voices an important part of the characters’ identities.
The new actors are therefore taking on roles with a considerable amount of history behind them.
Why Is the Voice Cast Changing?
The production team has explained that the decision is connected to the creation of the new television anime from scratch.
In the official announcement, the producers said that the cast of the new Keroro Gunso☆ would be completely changed, including the actors who had previously portrayed the Keroro Platoon.
The production team also expressed its sincere gratitude to the previous cast members for bringing the characters to life for so many years and helping them become beloved by audiences around the world.
This explanation is important because it makes clear that the new casting is part of a broader creative reset for the television anime.
It is not simply a case of one or two actors being replaced.
Instead, the new production is starting with a completely new central cast.
The Original Cast Has a Long History With Sgt. Frog
The original Japanese cast became closely connected with the Sgt. Frog characters over the course of many years.
The previous cast included:
- Kumiko Watanabe as Sergeant Keroro
- Etsuko Kozakura as Private Tamama
- Joji Nakata as Corporal Giroro
- Takehito Koyasu as Staff Sergeant Kururu
- Takeshi Kusao as Corporal Dororo
- Noriko Kuwashima as Fuyuki Hinata
- Chiwa Saito as Natsumi Hinata
The five Keroro Platoon actors in particular have been associated with their characters for roughly 20 years.
That long history explains why the casting announcement has generated such an emotional response among fans.
For viewers who grew up watching the original anime, the voices of Keroro and his platoon members are likely to be strongly connected with childhood memories.
The 2026 Movie Used the Original Cast
The timing of the change is particularly interesting because the franchise already returned to theaters earlier this year.
The new movie Shin Gekijoban☆ Keroro Gunso: Fukkatsu Shite Sokkō Chikyū Metsubō no Kiki de Arimasu! was released in Japan in June 2026 and featured the established cast.
That means the original and new versions of the franchise have appeared in the same year with different casting approaches.
The movie allowed longtime fans to hear the familiar voices again, while the upcoming TV anime represents the beginning of a new era for the television series.
This makes 2026 an especially important year in Sgt. Frog history.
Makoto Koichi Acknowledges the Emotional Side of the Change
Makoto Koichi, who will voice Sergeant Keroro, directly addressed the possibility that fans may feel sad or confused about the new casting.
Koichi said she understands those feelings herself.
At the same time, she emphasized that she wants to approach the role with respect for everything that has been built around Sgt. Frog over the years.
Rather than attempting to ignore the franchise’s history, she wants to take that history seriously while delivering her own performance as the new Keroro.
She also expressed hope that the new anime will become a weekly source of enjoyment for both longtime fans and people discovering Sgt. Frog for the first time.
That message reflects one of the major challenges facing the new production: respecting existing fans while also creating an accessible starting point for a new generation.
Rika Nagae Is Excited to Play Tamama
Rika Nagae, the new voice of Private Tamama, also expressed both excitement and a strong sense of responsibility.
Nagae said she was extremely happy and honored to join a series that has been loved by so many people since their childhood.
She specifically mentioned Tamama’s small body, enormous energy, cuteness, and explosive jealousy as qualities she wants to preserve.
At the same time, she said she wants to enjoy playing the character herself.
That balance—respecting the familiar personality while adding her own performance—is likely to be important throughout the new anime.
For viewers who are unfamiliar with Tamama, the character is one of the youngest-looking members of the Keroro Platoon.
Tamama’s adorable appearance contrasts with his surprisingly intense emotional reactions, particularly when jealousy or frustration takes over.
Toshiki Masuda Found a Personal Connection With Giroro
Toshiki Masuda, who will voice Corporal Giroro, shared one of the most personal comments among the new cast.
Masuda explained that he had enjoyed Sgt. Frog as both a manga and anime fan when he was younger.
After receiving the opportunity to audition for Giroro, he revisited the series from a different perspective.
Instead of simply viewing Giroro as a fictional character, Masuda began thinking about how he would approach the role if Giroro’s personality were his own.
He found similarities between himself and Giroro’s way of thinking and behavior.
Masuda said that even before the audition process had ended, he felt that Giroro was almost like his “other half.” He also said he would never forget the moment he learned that he had won the role.
His comments suggest that his connection with the character began well before he officially joined the cast.
Kosuke Echigoya Takes Over as Kururu
Kosuke Echigoya will voice Staff Sergeant Kururu, the eccentric technical genius of the Keroro Platoon.
Kururu is one of the more unusual members of the group, known for his intelligence, strange personality, inventions, and tendency to create problems through technology.
Echigoya described the opportunity as both a great honor and a major responsibility.
He emphasized that the series has been loved by audiences for a long time and said he intends to approach every part of the production carefully.
He also hopes the new anime will be enjoyable for both existing fans and newcomers.
That approach is particularly important for Kururu, whose distinctive personality and comedic timing are major parts of the character.
Keishi Inomata Becomes the New Dororo
Keishi Inomata will take over as Corporal Dororo.
The original text referred to the actor as “Keiji Inomata,” but official materials identify him as Keishi Inomata (猪股慧士).
Inomata said he feels honored to become part of the Keroro Platoon and acknowledged the long history the franchise has with its fans.
He also expressed his desire to make Dororo a character that both longtime viewers and future fans can continue to love.
Dororo is the skilled ninja of the group and is often portrayed as the quietest and most disciplined member of the platoon.
His serious personality creates an amusing contrast with the chaotic behavior of Keroro and the others.
The New Cast’s First Voices Can Be Heard in the PV
The first main promotional video gives fans an important preview of the new performances.
Rather than simply revealing the actors’ names, the PV features the characters speaking in their new voices.
This allows longtime viewers to begin getting used to the new performances before the October premiere.
For a franchise where voice performances have remained stable for decades, hearing the new actors in action is arguably more significant than simply seeing their names on a cast list.
The PV also introduces the overall tone of the new anime and provides a glimpse at the updated production.
A New Production Team Is Behind the Anime
The new series is being produced by BN Pictures.
The main staff includes:
- Original creator: Mine Yoshizaki
- Chief Director: Nobuhiro Kondo
- Director: Toshihiko Sano
- Series Composition: Toshimitsu Takeuchi
- Character Design: Hatsu Nakayama
- Color Design: Keiichi Funada
- Art Directors: Kenichi Tajiri and Shintaro Inoue
- Director of Photography: Teruyuki Kawase
- Editor: Daisuke Imai
- Sound Director: Akira Yamada
- Music: Kan Sawada
- Animation Production: BN Pictures
- Production Cooperation: Bridge and Aile
The involvement of a new staff lineup further reinforces the idea that Keroro Gunso☆ is intended as a new starting point.
At the same time, the original creator, Mine Yoshizaki, remains credited as the source of the franchise.
What Is Sgt. Frog About?
For people discovering the franchise for the first time, Sgt. Frog is a science-fiction comedy about a group of alien frog-like soldiers who come to Earth with the mission of conquering the planet.
The central character is Sergeant Keroro, the leader of the Keroro Platoon.
Unfortunately for Keroro, the invasion does not go according to plan.
He is separated from the rest of his forces and ends up stranded on Earth.
Instead of becoming a successful alien commander, Keroro finds himself living with the Hinata family, where he spends much of his time pursuing hobbies, creating ridiculous invasion plans, and getting into trouble.
His mission to conquer Earth never completely disappears.
However, everyday life often gets in the way.
The Keroro Platoon Is Not Exactly a Perfect Military Unit
The comedy comes largely from the fact that the Keroro Platoon is supposed to be an elite alien military unit—but frequently behaves more like a group of eccentric friends.
Keroro is obsessed with his plans and hobbies.
Tamama is energetic and emotionally unpredictable.
Giroro takes military discipline extremely seriously.
Kururu is a brilliant but strange inventor.
Dororo is skilled, quiet, and often overlooked.
Their personalities clash constantly, creating the situations that drive the series’ humor.
This makes Sgt. Frog easy for newcomers to enjoy even without knowing the entire history of the franchise.
The Original TV Anime Ran for Seven Years
The original Sgt. Frog TV anime began broadcasting in 2004 and continued for approximately seven years before ending its regular run in March 2011.
During that time, the franchise expanded into movies, merchandise, games, manga, collaborations, and other forms of media.
The characters became particularly recognizable in Japan, while the anime also developed an international fanbase.
The return of a new TV series after such a long gap is therefore a major event for the franchise.
The New Anime Is Designed for Both Old and New Fans
One of the biggest opportunities for Keroro Gunso☆ is its ability to introduce the franchise to younger viewers.
Someone who watched the original series in the 2000s may now be an adult.
A new generation of children and young anime fans may have never watched the original seven-year TV run.
A completely new production and voice cast provide an opportunity to present Keroro’s world in a way that does not require viewers to have followed the franchise for decades.
At the same time, the new cast’s comments repeatedly emphasize respect for longtime fans.
That balance could become one of the defining features of the new anime.
September 26 Advance Screening Announced
Fans in Japan will have a chance to watch the first two episodes before the television premiere.
An advance screening of Episodes 1 and 2 is scheduled for September 26, 2026, at United Cinemas Toyosu in Tokyo.
All five new Keroro Platoon voice actors are scheduled to attend:
- Makoto Koichi
- Rika Nagae
- Toshiki Masuda
- Kosuke Echigoya
- Keishi Inomata
A special cast talk will also be held during the event. The listed ticket price is ¥3,500, with lottery applications running from September 7 through September 13.
The screening willallow fansy to experience the new voices in full episodes before the official broadcast.
More News Is Coming on September 14
The September 7 announcement also confirmed that additional information about Keroro Gunso☆ will be released on September 14 at 5:00 p.m. JST.
The production team has not yet revealed exactly what the announcement will contain.
Therefore, fans will need to wait for the official update rather than relying on speculation about additional characters, music, or other details.
With the October premiere approaching, the promotional campaign is expected to intensify throughout September.
Why the Cast Change Matters So Much
Replacing a voice cast after approximately two decades is a major decision for any anime franchise.
In Sgt., it is particularly significant because the series is heavily dependent on character comedy.
Keroro’s personality is closely tied to his voice.
So are Tamama’s energetic reactions, Giroro’s seriousness, Kururu’s strange laughter and delivery, and Dororo’s quieter personality.
The new actors therefore face a difficult task.
They must make the characters recognizable without simply trying to imitate performances that have already become iconic.
The comments released with the casting announcement suggest that the actors understand this responsibility.
Their repeated emphasis on respect and gratitude indicates that they are approaching the roles with awareness of the franchise’s history.
A New Chapter Rather Than a Replacement of the Past
The new Sgt. Frog anime does not erase what came before it.
The original television series remains an important part of the franchise’s history, and the previous actors’ performances helped define the characters for millions of viewers.
Instead, Keroro Gunso☆ represents a new interpretation.
That distinction may help longtime fans approach the new series with a more open mind.
The new actors are not replacing the memories fans have of the original cast.
They are creating a new version of these characters for a new television series.
The voice-cast change for Keroro Gunso☆ is easily one of the biggest developments in the Sgt. Frog franchise in years.
After more than 15 years without a completely new regular TV anime, Keroro and his platoon are returning to television on October 3.
But they are returning with new voices.
Makoto Koichi will become Keroro, Rika Nagae will voice Tamama, Toshiki Masuda will play Giroro, Kosuke Echigoya will take over as Kururu, and Keishi Inomata will voice Dororo.
The new actors have already acknowledged that longtime viewers may feel sadness about the change, but they have also made it clear that they intend to treat the franchise’s history with respect.
The first PV gives fans a chance to hear their performances, while the September 26 advance screening will offer an even closer look at the new anime.
Meanwhile, another information announcement is scheduled for September 14.
For longtime fans, the October premiere will undoubtedly be an emotional experience.
For newcomers, however, it could be the perfect opportunity to discover the chaotic world of Keroro, Tamama, Giroro, Kururu, and Dororo for the first time.
After more than two decades of history, the Keroro Platoon is preparing to start a new chapter—and the new cast is ready to write it with them.
