Onosato studied painting with Tsuda Seifu (1880-1978), a well-known, western-style painter, and by 1935 had exhibited with the Nika artists' association, joining the Jiyu group in 1938. He served in Manchuria from 1941 to 1945 and was a prisoner-of-war in Siberia from 1945 to 1948. His painting was the Grand Prize winner at the 1963 Tokyo Biennial and his solo and group exhibition record in the ensuing decades is extensive. A museum dedicated to his work, The Onosato Museum of Modern Art, is in Gumma Prefecture, Japan.

Paintings by Onosato Toshinobu were sold in these Rooms, from the Estate of Blanchette H. Rockefeller, April 27, 1994, lots 19 and 31, and from the Onosato Museum of Modern Art, November 2, 1996, lot 486.