After breakup in the OST in 1931, Zernova joined the Izobrigada (“Group of art workers”).

In 1936 the first personal exhibition of the artist was held in Moscow.

In 1945–1953 Zernova taught at Moscow Institute of Applied and Decorative Arts (MIPiDI). She was also engaged in theatre and cinema. In 1947 she drew costume designs of Emilia to the performance South Junction; in 1957 she created a lot of sketches for the performance The Precipice in the Theatre of the Soviet Army.

In 1947 Zernova drew sketch for big painting Train station.

In late 1950s Zernova was invited to design pictorial and mosaic panels; since that time she worked as a monumental artist. Her panels were at the exhibition hall in Yalta, in Salavat, in the Institute of Oceanology and the Museum of Anthropology in Moscow.

In 1960s Zernova often painted in lyric style.

In 1970s she drew a series Miracles of Zoo in tempera. As she wrote, these illustrations were full of “emotional attitude to little animals”. The works from this series were exposed at Leonid Shishkin Gallery in 2006 and were published in album with the poems by A. Timofeevsky.

In 1974 Ekaterina Zernova was conferred a title of the Honoured Artist of RSFSR (Russian Soviet Federative Socialist Republic).

At the end of her life, Zernova wrote Memoirs of monumental artist.

Works by Ekaterina Zernova are in many museum collections, including the State Tretyakov Gallery, the Museum of Contemporary History of Russia (Moscow), Astrakhan Picture Gallery named after B. Kustodiev, the Art Museum of Karakalpakstan named after I. V. Savitsky (Nukus, Uzbekistan), the National Museum of Warsaw (Poland), and in private collections of Reynold Jonson and Matthew Bown.