Menachem Birnbaum, was an Austrian Jewish book illustrator and portrait painter.

Birnbaum was the second son of the Jewish philosopher Nathan Birnbaum and his wife Rosa Korngut. Birnbaum married Ernestine (Tina) Esther Helfmann, with whom he had two children: Rafael Zwi and Hana. Birnbaum lived in Berlin from 1911 until 1914 and again from 1919 until 1933. He then emigrated to the Netherlands. In the spring of 1943 he was arrested by the Gestapo and with his relatives transported on 10 March 1943 to a Nazi concentration camp - presumably Auschwitz.

Menachem was seen alive and spoken to in Auschwitz in October 1944 by a Dutch Jewish survivor, who told this to his brother Uriel Birnbaum in Holland after WW2. His family Tina, Rafael Zwi, and Hana Birnbaum were killed earlier (probably in Auschwitz also). Therefore he must have died between October 1944 and January 27, 1945 - when Auschwitz was liberated by the Soviets. It is likely that he died during or just before the Death March from Auschwitz in mid-January, 1945. Therefore the information that he died in the Sobibor extermination camp is incorrect. It is based solely on an unconfirmed assumption by the Red Cross that the trains from the German holding camp at Westerbork, Holland went to Sobibor on that day.