Masaki Aiba (相葉 雅紀, Aiba Masaki) (born December 24, 1982) is a Japanese singer, actor, television personality, radio host and dancer under Johnny & Associates, later of Starto Entertainment. He was a member of the boy band Arashi until the end of activities of the group, May 31, 2026.
Aiba began his career in the entertainment industry when he joined the Japanese talent agency Johnny & Associates in 1996, at the age of 13. Prior to his debut with Arashi in 1999, Aiba started an acting career when he was cast as the lead role of Gordie for the stage play Stand by Me, based on the film of the same name. In 2004, he became one of the co-hosts of the variety show Tensai Shimura Dōbutsuen (天才！志村どうぶつ園, Genius! Shimura Zoo), making him the first member of Arashi to regularly participate in a variety show not primarily hosted by Arashi.
Early life
Aiba was born in Hanamigawa, Chiba as the first child of his family. He has a younger brother who is four years younger. Aiba was raised by his grandparents until he was four years old because his parents were busy running their newly opened Chinese cuisine restaurant then.
Prior to joining Johnny & Associates, Aiba watched a program called Love Love SMAP (愛ラブSMAP, Ai Rabu SMAP) and saw SMAP playing basketball on television. Wanting to play basketball with them, he sent in the application to join the talent agency himself, without exactly knowing what the agency specialized in until the day of auditions. Aiba became a Johnny's Jr. in August 1996 at the age of 13.
Music career
In collaboration with the other members, he has written the lyrics to "Fight Song" and "5x10".
For his solo song "Hello Goodbye", Aiba played the blues harp harmonica in the interlude portion of the song. Aiba also used to play the saxophone; however, due to the collapse of one of his lungs in 2002, he was forced to stop playing.
Stage
Aiba began acting in a 1997 stage play based on an American coming of age film called Stand by Me with future bandmates Jun Matsumoto and Kazunari Ninomiya.
In 2005, Aiba took up the lead role of Keiji Takashima (高島 啓治, Takashima Keiji), a naive but honest station attendant living in a world after a World War III nuclear war, in Tsubame no Iru Eki (燕のいる駅, A Station with Swallows).
In 2007, Aiba portrayed Adam, a shy young man with a heart defect, in Wasurerarenai Hito (忘れられない人, Unforgettable Person). It was the first stage adaptation of the 1993 film Untamed Heart.
In early 2008, Aiba was given the lead role of Colin Briggs in the stage play called Greenfingers, which was adapted from the movie of the same name.
Aiba reunited with director Keiko Miyata (宮田 慶子, Miyata Keiko), who has been the director for his stage plays since 2005, and took on the lead role for Kimi to Miru Sen no Yume (君と見る千の夢, The Thousand Dreams I Dream With You), which ran from May 5 to 24, 2010. He portrayed a young man hovering over life and death due to a violent traffic accident.
In October 2024, Aiba took the role of Psychologist Edmund Einhard in Sony Music Group's room NB's project Reading High noir reading play "Thanatos", sharing the stage with Akio Otsuka and Saori Hayami. It is the first time Aiba participates in this kind of stage play.
Drama
In 1997, Aiba made his drama debut portraying Akira, one of the many children left to survive in a city under government lockdown after a mysterious disease wipes out all the adults, in the drama Bokura no Yūki: Miman Toshi (ぼくらの勇気, Our Courage: Miman City). After the announcement of the formation of Arashi in September 1999 and their position as supporters for the 1999 Volleyball World Cup competition, all five members starred together for the first time in the volleyball-centered short drama V no Arashi.
Although Aiba was featured in a number of dramas such as Mukodono 2003 (ムコ殿2003, The Son-in-Law 2003) and Yankee Bokō ni Kaeru (ヤンキー母校に帰る, Drop-out Teacher Returns to School), he became more known for his appearances in variety shows instead and went on to focus on stage productions after Yankee Bokō ni Kaeru.
On August 2, 2009, it was announced that Aiba would not only act in his first drama series in nearly six years but also star as the lead actor for the first time. In My Girl, Aiba portrayed a young man who discovers that he has a five-year-old daughter after receiving the news that his girlfriend, who he has not seen in six years, was killed in an accident.
In January 2010, Aiba co-starred with the other members of Arashi in the human suspense drama special Saigo no Yakusoku. He portrayed Akira Tanada (棚田 昭, Tanada Akira), a 28-year-old coffee shop employee who is caught up in a building hijack. Starting January 2011, Aiba starred as genius bartender Ryū Sasakura (佐々 倉溜, Sasakura Ryū) in the drama adaptation of the manga Bartender. Aiba also made a guest appearance on the final episode of bandmate Ninomiya's drama Freeter, Ie o Kau (フリーター、家を買う。, Part-time Worker, Buys a House), which aired on December 21, 2010.
In April 2012, Aiba once again starred in a lead role as "Katayama Yoshitaro" in the NTV drama adaption of the similarly named novel series, " Mikeneko Holmes no Suiri (三毛猫ホームズの推理).
In 2013, took the lead role as a doctor in "Last Hope".
Film
In 2002, he made his motion picture debut in Pikanchi Life is Hard Dakedo Happy (ピカ☆ンチ Life is HardだけどHappy, Pikanchi Life is Hard But Happy), Arashi's first movie together, as the lead character Shun. He subsequently reprised his role for the 2004 sequel Pikanchi Life is Hard Dakara Happy (ピカ☆☆ンチ Life is HardだからHappy, Pikanchi Life is Hard Therefore Happy).
The group once again came together in 2007 to co-star in Kiiroi Namida (黄色い涙, Yellow Tears) with Aiba portraying an aspiring singer in the 1960s.
Animation
Aiba's debut as voice actor for a full-length animation film is with "Pui Pui Molcar The Movie ~ Molmax", a CG version of the series, released on November 29, 2024. Aiba has appeared in anime before, in one episode of KochiKame anime, with the other members of Arashi, in a mini sketch before the ending song Nice na Kokoroiki, which is sung by the group; in Crayon Shin-chan, in a short at the end of episode 983, as his character from his drama Boku to Shippo to Kagurazaka, and as character inspiration and voice actor for Koikeya SDGs Theater Suss and Tena, a mini anime from snack company Koikeya Inc.. For Molcar's movie, Aiba will play a human character in the Molcar's world. Details of the movie and of his character have not been revealed yet.
Radio
Since October 5, 2001, Aiba has his own radio show Arashi's Aiba Masaki no Rekomen! Arashi Remix, which currently broadcasts on JOQR. On August 7, 2026, it was announced that the program would end at the end of September, closing a 25 year history with the station. Regarding this, Aiba commented that he would like to do another radio program in the future, as well as something with Nippon Cultural Broadcasting.
On May 17, 2009, Aiba hosted a special radio program on Tokyo FM called Muteki no Aiba-kun (ムテキの相葉クン!, Invincible Aiba).
Variety show host
In 2004 Aiba became a regular part of Ken Shimura's variety show Tensai! Shimura Dōbutsuen. With co-hosts of the show such as Tomomitsu Yamaguchi, Sayaka Aoki and Becky, Aiba interacts with various wild animals such as tigers, pandas and crocodiles in zoos both in and out of Japan, such as Singapore, South Africa, Philippines and Indonesia. After Shimura's passing on March 29, 2020, Aiba was given the lead of the show. The name for the show remained as a tribute to Shimura. As of June 3, 2020, NTV decided to end broadcasting "Tensai!" in September, stating as a reason that to continue filming on that stage, with all the memories gathered throughout almost 16 years that the show was on air, would be painfully difficult and heartbreaking. However, Aiba would continue as host of a new program with basically the same theme: the love for animals. The new show, I love みんなのどうぶつ園 (I love minna no doubutsuen), started…