Nobuyo Yamashita (山下 羨代, Yamashita Nobuyo; née Ōyama, October 16, 1933 – September 29, 2024), known professionally as Nobuyo Ōyama (大山 のぶ代, Ōyama Nobuyo), was a Japanese actress last affiliated with Actors Seven. Her husband was actor and television personality Keisuke Sagawa. She is best known for voicing Doraemon, the titular character of the Doraemon franchise from 1979 to 2005 and Monokuma, the main antagonist of the Danganronpa franchise from 2010 to 2016.
Contents
Biography
Early life
Ōyama was born as the thirteenth in a four-generation family of thirteen people on October 16, 1933. Her great-grandparents were born in the Edo period of Japan and her mother was the daughter of a sake brewer in Furukawa City, Miyagi Prefecture (now Ōsaki, Miyagi City).
She graduated from Rinkawa Elementary School, Hiroo Elementary School, Hiroo Junior High School and Mita High School, Tokyo.
Since an early age, she had a distinctive voice, and when she answered the phone at her kindergarten entrance ceremony, all of the students' parents all stood up and stared. However Ōyama herself was oblivious to reactions. She was such a talkative person that her mother would often tell her, "If you are quiet for a while, I'll give you a treat."
As she entered elementary school, Ōyama was initially an active girl who would run around the schoolyard raising her voice, but people around her would often tell her that she had a "boy's voice," and her teachers gave her strange looks when she checked in for her attendance, so she began to think her voice was strange.
Once Ōyama entered junior high school, a classmate pointed out how her voice was, and that is when she started to become aware of her unique voice. She started to feel disgusted by her voice, and became a quieter person.
She was bullied by her school classmates because of her voice, with a game of "everyone will laugh when Ōyama makes a sound" becoming popular in class. She grew withdrawn, but her mother advised her, "Just because you have a strange voice, if you keep coddling that weakness, it will only get weaker. Join a club activity where you have to use your voice."
Ōyama became satisfied with her voice over time, and was able to overcome her complex. However, she never expected to become a voice actress. Her surrounding peers and homeroom teacher were initially opposed to her school activities, though after a month, they stopped saying their objections, and Ōyama was soon invited to join the school's drama club. Her stage debut was the role of the wicked stepmother in the school's play of Cinderella.
Career
Following high school, Ōyama entered the Haiyuza Training School as a member of the seventh batch, but her father, who was against these plans, told her, "If you want to be an actor, get out!", so she ran away from home and started living alone. She quickly realized that she would be unable to survive solely on the money that was sent to her from her supportive older brother, so she tried various part-time jobs to earn money for living. Her classmates there included Kumi Mizuno, Shigeru Tsuyuguchi, Hisashi Igawa, Manabu Yamamoto, Shigeyoshi Fujioka, and Kunie Tanaka.
She made her debut in the NHK drama Kono Hitomi in 1956. She began her acting career while in the training school, and after graduating in 1957, she joined the theater company Shinjinkai.
When Ōyama started her career, she received praise as "a funny kid" and "a comedian with a background in modern theater", and appeared in many dramas and comedy shows. She began her voice acting career after a friend noticed her unique husky voice and told her that her voice suited young male roles. Her voice acting debut was in the Japanese dub of Lassie, which aired in September 1957.
In 1960, Ōyama voiced the character Boo in the Japanese puppet show Boo Foo Woo, which led to an increase in voice work.
In 1965, Ōyama made her debut as a lead voice actor in the television anime Hustle Punch, where she voiced the character Hustle. After that, she then starred in several anime productions such as Harris no Kaze and Invincible Super Man Zambot 3.
She was affiliated with Tokyo Pro, Gekidan Deku, Takamatsu Riyuko Office, and Aoni Production.
In late 1978, she was officially cast as the voice of the titular character in the Doraemon anime series, which premiered on TV Asahi the next year. It became her most popular work.
She also became active in a wide range of fields other than voice acting, such as working as a TV personality and publishing books as a cooking expert.
After Doraemon
After leaving the Doraemon franchise, Ōyama focused on giving lectures and making television and radio appearances. She also continued her voice acting work, narrating shows such as Gansou! Debuya.
In March 2005, Ōyama received the Broadcasting Woman Award.
In May 2006, Ōyama published an autobiographical essay titled, I Was Doraemon. 26 Years of Tears and Laughter which focused on detailing her 26 years voicing Doraemon and was published by Shogakukan.
Six months later, she was awarded a special prize at the 11th Kobe Animation Awards for her achievements on Doraemon alongside her Doraemon co-stars Noriko Ohara, Michiko Nomura, Kaneta Kimotsuki, and Kazuya Tatekabe. The following year in March 2007, they received the Merit Award of the Tokyo Anime Awards at the Tokyo International Anime Fair.
In April 2007, Ōyama became principal of the Acoustic Arts College in Nishi-Shinbashi, Minato-ku, Tokyo. In addition to organizing the curriculum, she also taught many day and night classes for the voice actor and announcer courses, providing direct instructions to students.
On April 24, 2008, while preparing for class in the principal's office at the Acoustic Arts College, Ōyama suffered a cerebral infarction and was hospitalized, but with proper medication, she was discharged on August 17. Through home recuperation and rehabilitation, she ended up recovering to where she was able to carry out daily activities without worry.
In 2010, Ōyama portrayed the antagonist Monokuma in the PSP video game Danganronpa: Trigger Happy Havoc. She continued to voice Monokuma in the Danganronpa franchise, and in 2013, the series was made into an television anime adaptation entitled Danganronpa: The Animation, which was both her first TV anime appearance since Doraemon and her first appearance in a late-night television anime.
In April 2011, Ōyama decided to step down from her position as principal of the Acoustic Arts College and became its honorary president. Though she stepped back from most practical duties, she continued to give special lectures once every few months until 2013. Around this time, she started limiting her work, citing poor health caused by a busy and intense work schedule.
Final years
In the fall of 2012, Ōyama was diagnosed with Alzheimer's disease. Initially, her husband Keisuke Sagawa was worried that it would "tarnish the image of Doraemon and her", so the diagnosis was kept secret for a few years. However, after he received advice from fellow actor Sandayū Dokumamushi, he reconsidered, and on May 13, 2015, Sagawa publicly announced Ōyama's diagnosis during a guest appearance on TBS Radio's Ōsawa Yūri no Yūyū Wide program. At the time the announcement was made public, Ōyama said that she had already forgot that she and her husband discussed it.
Although she continued to work after the announcement, she stopped making public appearances and work was limited to recording messages. From 2014 to 2016, Ōyama appeared in the National Federation of Agricultural Cooperative Associations' web anime I Love Meat! Zeushi-kun as Minota, but this ended up being her final anime voice acting role.
On June 12, 2015, Sagawa appeared on Tetsuko Kuroyanagi's show Tetsuko's Room, of which he had made previous appearances on many times with Ōyama. Ōyama sent a voice message to Kuroyanagi.
During the broadcast, she realized that her illness was made public, and remarked, "Why did they make such a big deal out of this?" Afterwards, Sagawa told her, "It's not an exaggeration at all," and "In order to cheer her up, we need to make sure people know the truth, so we can do our best," to which Ōyama replied back, "Yeah, I'll do my best."
Following Ōyama's wishes, she was cared for at home by Sagawa, the couple's manager Akiko Kobayashi, and a housekeeper for a while after the onset. However, Sagawa started to receive treatment for ureteral cancer, so she entered a nursing home in April 2016. That month, Ōyama's role of Monokuma in the Danganronpa franchise was recast with Tarako. Ōyama officially announced her retirement in December.
Sagawa died on July 11, 2017, at the age of 80. After Sagawa's death, Ōyama continued to live in the nursing home, and was looked after by Kobayashi. While her dementia was progressing, she was in overall good health, and enjoyed interacting with other residents, taking on a leadership role in activities such as singing in choir.
Death
Ōyama died of senility in Tokyo on September 29, 2024, at the age of 90. Actors Seven announced her death that October, and many animators, voice actors, and fans paid tribute to her on social media. Later in the month, a dedication to Ōyama was shown during the broadcasting of Doraemon and Sazae-san.
The Fujiko F. Fujio Museum and Doraemon's current voice actress Wasabi Mizuta also wrote eulogies for her.
Her grave is located at Daiunji Temple, Shibuya Ward.
In April 2026, it was reported in "Josei Seven Plus" that her home located in Tokyo was sold in February of that year and because there are no heirs following both her and Sagawa's deaths, the entire estate has been turned over to the national treasury.
Personality
Her voice range was alto.
As a voice actress, Ōyama had been active since the dawn of television anime. Her unique way of laughter, which sounds like either "uhihi" or "ufufu", has been praised and regarded as a memorable characteristic.
In many of her non-Doraemon roles, she voiced young boy characters, and was known for her husky, mischievous way of talking, and used a rough and tumble manner of speaking.
Ōyama's personal motto was "I want to be a pipe", which reflected her desire to pass down knowledge such as legends and proverbs she inherited from her predecessors onto the next generation.
Successors
Due to Ōyama's decision to solely focus on Doraemon and her subsequent aging, the following individuals have taken over some of her voice acting roles.
Legacy and accolades
Ōyama was best known for voicing Doraemon in the Doraemon franchise from 1979 to 2005 and Monokuma in the Danganronpa franchise from 2010 to 2016. Ōyama is known as the voice of Doraemon by many Doraemon fans and is popular in the Danganronpa fandom for her performance.
She was also a culinary expert and often published books of her own, such as Nobuyo Ōyama's Interesting Sake and Food, which ended up selling over 1.36 million copies, becoming a bestseller.
In February 2022, Fuji TV aired a variety show, This Is A Classic! Best Anime Entertainment Generation By Generation, where a survey was held for "favorite voice actors" from different generations over the decades and Ōyama came in first place in the Showa generation category.
In March 2025, she and Doraemon co-star Noriko Ohara posthumously received the "Special Award from the Chairman" at the 48th Japan Academy Film Prize for "outstanding contributions and outstanding results in the film industry over many years". That same month, actor Sandayū Dokumamushi made a guest appearance in an episode of the television program Tetsuko's Room as a representative of Ōyama's close friends, where he discussed personal memories with Ōyama with the show's hostess Tetsuko Kuroyanagi, whom Ōyama had co-starred with in the NHK costume puppet segments Boo Foo Woo on Okaasan to Issho.
In September 2025, on the one year anniversary of her death, a memorial gathering for Ōyama was held. Several close friends and colleagues, such as Michiko Nomura, Wasabi Mizuta, Michio Hazama, Masako Nozawa, Mari Shimizu, Miyuki Ueda, and Eiko Yamada attended the service.
















