Yoshio Otomo (大友義雄, also romanised Ohtomo) is a Tokyo alto and soprano saxophonist who has been working the city's clubs and studios since the early 1970s. He was born in Tokyo on March 31, 1947, the youngest of three brothers. His official biography says his mother was a teacher of kouta, the short shamisen songs of the Edo tradition, and that his brothers played flute and clarinet. He started on piano at about five, taught himself clarinet in junior high school and played in the brass band, then switched to saxophone on entering Gyosei High School (暁星高校), where he began playing jazz at school festivals.

At Nihon University's College of Art he met an older clarinetist, Eiji Hanaoka (花岡英二), and began playing jazz seriously. The pianist Fumio Itabashi noticed him and brought him into his quintet, which is how his official biography and the Japan Jazz Music Association both describe his entry into the Tokyo scene. The decisive influence was Sadao Watanabe: hearing Watanabe play live after his return from Berklee convinced him to turn professional, and he later joined the theory course Watanabe ran. By his own account he formed a group of his own in the mid-1960s, and his official biography says he became known for choosing young players who went on to make careers. The trombonist Shigeharu Mukai lists Otomo's group among the bands he worked in after moving to Tokyo in 1971.

His earliest recording credit on Discogs is a live album, South, cut at the jazz club Rob-Roy in Aoyama on February 19, 1974, behind the vocalist Minami Yasuda, with the Tsuyoshi Yamamoto trio of Isoo Fukui on bass and Tetsujiro Obara on drums. A month later he was on stage at Nihon Toshi Center Hall for the Three Blind Mice "5 Days in Jazz" recordings. On March 23 and 26, 1974 he played alto in the Takashi Mizuhashi quartet with Fumio Karashima on piano and Hideo Sekine on drums, and on the long closing track "Sugar" the tenor saxophonist Seiichi Nakamura and Mukai joined in. The label issued it as When a Man Loves a Woman. His official biography calls it his defining performance, and the Japan Jazz Music Association still describes it as a historic one. On March 26 he also played on the second side of Now's the Time, the George Otsuka quintet side of a shared Three Blind Mice record, next to the tenor saxophonists Takao Uematsu and Mabumi Yamaguchi and the alto saxophonist Kenji Mori. That August 28 he recorded Who Cares with the Mizuhashi quartet at Aoi Studio.

In 1975 he made a twin-alto record with Hidefumi Toki. Lover Man, billed to Yoshio Otomo/Hidefumi Toki Alto-Madness, was recorded on May 26, 1975 at Toshi Center Hall for Three Blind Mice, with Kazumi Watanabe on guitar, Nobuyoshi Ino on bass and the American drummer Steve Jackson. Its three tracks are "Scrapple From the Apple," "Lover Man" and a nineteen-minute blues, "Blues for T & O."

His own quartet records followed. Oh! Friends (Frasco, FS-7010) was recorded at Victor Studio on January 21 and 22, 1976 and presented by Pit Inn Music, with Junichiro Ohkuchi on piano, Satoshi Kosugi on bass and Fumio Watanabe on drums. Moon Ray (Three Blind Mice, TBM-3007) was recorded at Epicurus Studio on April 21 and 22, 1977, billed as the Yoshio Otomo Quartet with Tsuyoshi Yamamoto, and has Tamio Kawabata on bass and O. "Jess" Kurata on drums. Its five tracks are "Moon Ray," "Emily," "If I Should Lose You," "Love Comes Quietly" and Oliver Nelson's "Shufflin'." As A Child (Seven Seas, SKS-3003, 1978) changed the setting to an electric rhythm section of Toshiyuki Sekine on electric piano, Kosugi on electric bass and Akiyoshi Yoshino on drums, with Otomo on both alto and soprano.

From the late 1970s he was also a regular in big bands and studio sections. He is one of the two alto saxophonists on George Kawaguchi's Super George & The Super Band (recorded June 25 and 26, 1979), alongside Hidehiko Matsumoto, Yasuaki Shimizu and Isao Suzuki, and on Super Drums 2: Tribute to Gene Krupa (February 15 and 16, 1983) and the promotional DHL Presents George Kawaguchi Super Big Band (January 16 to 18, 1986), for which Hiromasa Suzuki and Norio Maeda wrote the arrangements and Tatsuya Takahashi is credited as leader and on tenor saxophone and clarinet. Earlier, in 1976, he was the alto saxophonist on Kawaguchi's two-drummer record with Motohiko Hino for Teichiku. On March 13 to 15, 1979 he played soprano saxophone on Itabashi's Nature at Nippon Columbia's 1st Studio, with Hiroshi Hatsuyama on vibraphone and Ryojiro Furusawa among the drummers.

The film work came in 1986. The Kadokawa film Cabaret produced a CBS/Sony soundtrack album on which the Yoshio Otomo Quartet is featured on three tracks, "K's Bar," "Into the Night" and "Peek-A-Boo," with Otomo credited as arranger on all three and as performer on two. His official biography says he served as music director of the film. The same year he was a guest on three tracks of Toshio Osumi's The Melodies of Love, on alto and soprano. In 1987 he is one of the alto players in the sax section of Mr. Soul Man, led by Nobuo Hara with arrangements by Maeda and Kiyoshi Sugimoto on guitar.

The later decades are mostly sideman work for other leaders. He plays on the pianist Ritsuko Endou's two albums with her band Funky Ritsuco Version!, Sunshine (Break Time, recorded January 27 and 28, 1992, on which he is also credited as musical supervisor) and FRV! (Denon, 1997). He is on Masaru Imada's NOWIN album Lovers in the Storm (Venus Records, 1996), on Shigeo Maruyama's large-ensemble records A Young Father's Song (1981), with Koichi Matsukaze and Kazutoki Umezu in the band, and Kick Off, recorded with Matsukaze at the 2nd Yamaha Jazz Festival in Hamamatsu on April 18, 1993, on the vocalist Kei Hoshino's In A Sentimental Mood (2006), and, most recently on Discogs, on the vocalist Sayoko Shimohsa's Keep Steppin' (Grace Notes, January 2020), with Yamamoto on piano and Osumi on drums.

In 2023 the Japan Jazz Music Association gave him one of its Jazz Awards (ジャズ大賞), shared that year with the bassist Sachio Akiyama and with Yamamoto; he announced the award on his official site on October 31, 2023. The association's profile describes him as a player of the "crying sax" (泣きのサックス), soulful, sometimes fierce and sometimes aching, and says he has a following overseas. His official profile lists performances in New Caledonia, China, Malaysia, France, South Korea, Cuba and Colombia. He teaches jazz saxophone in Tokyo, including at the Yamaha Music Avenue Shinjuku Rifra Plus school, and in August 2026, at 79, he was still updating his live schedule on his official site.

Otomo is an alto player first, with a bright, high tone and a shimmering upper register. The writer Kozo Watanabe, who first heard him at Shinjuku Pit Inn with the Mizuhashi quartet, wrote in a 2017 column on Moon Ray that his improvised phrasing resembled Sadao Watanabe's and that he was "very skilled." The official biography ties the style to Watanabe directly, and calls his sound soulful and emotional, which is where the "crying sax" tag comes from.

Discogs files Oh! Friends under hard bop and post-bop, Who Cares under post-bop and modal, and As A Child under bop and jazz-funk, which fits the range on the records: standards-heavy quartet dates for Three Blind Mice and Frasco, a modal-leaning studio session with Mizuhashi, a twin-alto set with Toki, an electric-piano quartet in 1978, and then forty years of section and guest work in big bands, vocal albums and fusion bands. His repertoire is the usual one of the period: "If I Should Lose You," "In A Sentimental Mood," "Emily" and "Green Dolphin Street" all turn up on his records.