Marian Teodor Ludwik Gieszczykiewicz (born May 21, 1889 in Kraków, Austria-Hungary - July 30, 1942 in Auschwitz) was a Polish physician, bacteriologist.
Gieszczykiewicz was professor at the Jagiellonian University starting in 1924 and member of the Polish Academy of Skills. During the German occupation he taught at the so-called "Secret Universities".
He was imprisoned and died in the German concentration camp Auschwitz.