From the Jewish Partisan Encyclopedia
They were Jews in Europe, many of them teenagers, male and female, who fought against the Nazis during World War 2. The majority were regular folks who escaped the ghettos and work camps and joined organized resistance groups in the forests and urban underground.
Some, like Polish teenager Frank Blaichman, knew their village would be turned into a ghetto; He escaped and joined a group of partisans in a forest. Others, like Abe Asner, were among the very few Jewish partisans with military training. Most partisans knew nothing about guns and ammunition, so people like Abe became important teachers and leaders.
Less than ten percent of the partisans were women. Some were fighters and scouts; the majority were part of the vital infrastructure, cooking for the group and caring for the sick.
Jews who joined non-Jewish partisan groups often hid their Judaism because of antisemitism. Norman Salsitz, for example, used seven non-Jewish identities while fighting the Nazis and was able to save dozens of Jews from certain death.