Born in Moscow, Nikolai Sapunov studied at the Moscow School of Painting, Sculpture and Architecture under Levitan (1893-1901), and at the Academy of Arts (1898-1901) under Kiseliov.

He painted sets for Bolshoi Theatre, Moscow based on designs by Korovin (1901-1902), as well as for Moscow Art Theatre (from 1904), the sets and costumes for Meyerhold's 1906 production of Alexander Blok's The Puppet Show, and theatres of Vera Komissarzhevskaya and experimental Theatre of Alexandr Tairov.

Sapunov painted still life with flowers and china, and compositions on theatrical themes. His best known paintings are the magnificent stills with flowers and china. From 1918 he participated in exhibitions including Crimson Rose, World of Art, Blue Rose, Moscow Society of Artists.

At the end of his life he began a series of ironic genre pictures, that was left unfinished, as was his wish to go abroad. Nikolai Sapunov drowned in a boating accident in Terioki, Finland (now St.Petersburg district), aged 32.