The Canadian-born actor gave life to Optimus Prime for four decades and also became a familiar voice as Disney’s Eeyore.
LOS ANGELES, Calif. — Peter Cullen, the veteran voice actor whose commanding baritone defined Optimus Prime for generations of “Transformers” fans, died Wednesday at his Los Angeles home, his representative confirmed. He was 85.
Cullen died Aug. 26 surrounded by his family, according to a statement shared by his agent, Kevin Motley. A cause of death had not been disclosed Thursday. Cullen spent decades working across animation, television, film and video games, but his performance as the heroic leader of the Autobots became the role most closely tied to his career. He first voiced Optimus Prime in the original 1984 animated “Transformers” series and repeatedly returned to the character over the next four decades.
Cullen’s family remembered him as someone whose values extended beyond the characters he portrayed. In its statement, the family encouraged people honoring his legacy to serve their communities and lead with compassion, integrity and loyalty. The statement ended with a phrase strongly associated with Cullen’s approach to Optimus Prime: “be strong enough to be gentle.” The idea came from advice Cullen said he received from his older brother Larry, a U.S. Marine who served during the Vietnam War.
Cullen often explained that Larry shaped the voice and personality he brought to Optimus Prime. Before the original audition, Cullen knew he was trying out for the leader of a group of transforming robots. Rather than using the exaggerated voice of a traditional action hero, he drew on his brother’s calm authority. Cullen later said Larry taught him that a real hero did not need to shout to demonstrate strength. That approach helped create the deep, measured voice that became one of the most recognizable elements of the “Transformers” franchise.
His work as Optimus Prime began with the syndicated animated series in 1984. Cullen continued in “The Transformers: The Movie” in 1986 and later returned when director Michael Bay brought the property to live-action theaters in 2007. His voice was heard through multiple films that followed, including “Transformers: Revenge of the Fallen,” “Dark of the Moon,” “Age of Extinction,” “The Last Knight,” “Bumblebee” and “Transformers: Rise of the Beasts” in 2023. He also played the character in animated productions, video games and other franchise projects.
Optimus Prime was only one part of a career that covered a wide range of characters and styles. Cullen became well known to another generation of viewers as the voice of Eeyore, the gloomy but gentle donkey in Disney’s Winnie the Pooh productions. He voiced Eeyore in “The New Adventures of Winnie the Pooh,” which aired from 1988 to 1991, and returned to the character in other television programs, films, shorts and games. Cullen said in past interviews that Eeyore was among his favorite roles outside of Optimus Prime.
Other credits demonstrated the range of Cullen’s voice work. He supplied the voice of the villainous vehicle KARR in “Knight Rider,” performed vocal work for King Kong in the 1976 remake and contributed creature sounds to the 1987 film “Predator.” His television work also included projects connected to “G.I. Joe,” “The Smurfs,” “DuckTales” and “Chip ’n Dale: Rescue Rangers.” Before becoming established as a full-time voice actor, Cullen worked as an announcer and performer on television variety programs.
Born in Montreal, Cullen developed his talent for voices while still young. He later studied acting at the National Theatre School of Canada and graduated in 1963. An official Emmy Awards profile said he worked in Canadian radio and television before moving his family to Hollywood in 1971. Voice-over work eventually became the center of his career, and by the late 1970s and early 1980s he was regularly working on commercials, trailers and animated television projects.
The entertainment industry recognized Cullen’s long career in 2023 when the National Academy of Television Arts & Sciences presented him with a Lifetime Achievement Award at the second annual Children’s & Family Emmy Awards. His longtime “Transformers” colleague Frank Welker, the voice actor best known in the franchise as Megatron, presented the honor. The award came nearly four decades after Cullen first entered the recording booth as Optimus Prime and reflected a career that crossed generations of television and movie audiences.
Cullen also developed an unusually close relationship with fans of the characters he voiced. He frequently appeared at conventions and fan gatherings, where adults who had grown up watching “Transformers” introduced the actor to their own children. Cullen said those meetings could become emotional for both him and the fans because the character had remained part of their lives for decades. Optimus Prime’s continued appearances in movies, television series and games allowed Cullen’s performance to reach audiences far beyond those who watched the original cartoon.
Cullen is survived by his four children, Angus, Claire, Pilar and Clay. His family had not announced a cause of death as of Thursday. Cullen leaves behind a voice-acting career spanning more than five decades and a performance as Optimus Prime that remained closely associated with the character from the franchise’s earliest television years through its modern film era.
Author note: Last updated August 27, 2026.