Otakar Mrkvička (Příbram, 1898 – Prague, 1957) was a painter, illustrator, stage designer, art critic and theorist. He is considered to be one of the pioneers of primitivism, and poeticism. 

Mrkvička studied at the Academy of Visual Arts in Prague and the College of Art and Design from 1919 to 1922. Later, he studied at the Academy of Art in Munich (1924 – 1925).

He was a part of Devětstil and soon became of its most prominent members. The art association Devětsil (Umělecký Svaz Devětsil) gathered artists of different poetics, but all with Marxist orientation and well connected with the international avant-garde movements. With Karel Teige, he collaborated extensively in the programmes of lectures on art, organized by Devětsil.

Since the mid-1920s he worked as a stage designer for the Liberated Theatre (directors Jindřich Honzl and Jiři Frejka) and later collaborated with Dada theatre.

Mrkvička spent most of his life working on book illustrations, illustrating over seventy books by renowned Czech and international writers. With Karel Teige, he designed several constructivist book covers. Some of the publications he illustrated include Jaroslav Seifert, Samá Lásk, 1923; Guillaume Apollinaire, Zavražděný básník, 1925, and Karel Konrád, Rinaldino, 1927 (both with Teige).

Mrkvička was the co-founder of the left-wing satirical journal Trn (1924) and created caricatures and political drawings for it. In the 1930s, Mrkvička's journalistic activity culminated. His satirical drawings, caricatures, portraits and critiques appear in Lidový noviny, and his name is synonymous with the words journalist and draftsman.