Maria (Marianna) Trzcinska (22 March 1931 - 22 December 2011 in Warsaw) was a Polish judge employed for over 30 years in the People's Republic of Poland at the Main Commission for the Investigation of Nazi Crimes in Poland (Glówna Komisja Badania Zbrodni Hitlerowskich w Polsce).
She investigated and researched the Nazi German World War II crimes in Poland.
Trzcinska was the author of a monograph about the Warsaw concentration camp (KL Warschau) set up by the SS in occupied Poland, which was rejected by mainstream historians.