Kazimierz Zarankiewicz (2 May 1902 – 5 September 1959) was a Polish mathematician, interested primarily in topology.
Zarankiewicz was born in . He studied at the University of Warsaw, together with Zygmunt Janiszewski, Stefan Mazurkiewicz, Wacław Sierpiński, Kazimierz Kuratowski, and Stanisław Saks.
During World War II, Zarankiewicz took part in illegal teaching, forbidden by the German authorities, and eventually was sent to a concentration camp. He successfully survived and became a teacher at Warsaw University of Technology.
He visited universities in Tomsk, Harvard, London, Vienna. He served as president of the Warsaw section of the Polish Mathematical Society and the International Astronautical Federation.
Zarankiewicz wrote works on cut-points in connected spaces, on conformal mappings, on complex functions and number theory, and triangular numbers.