Jewish partisans were fighters in irregular military groups participating in the Jewish resistance movement against Nazi Germany and its collaborators during World War II.

A number of Jewish partisan groups operated across Nazi-occupied Europe, some made up of a few escapees from the Jewish ghettos or concentration camps, while others, such as Bielski partisans, numbered in the hundreds and included women and children. They were most numerous in Eastern Europe, but groups also existed in occupied France and Belgium, where they worked with the local resistance. Many individual Jewish fighters took part in the other partisan movements in other occupied countries. In total, the Jewish partisans numbered between 20,000 and 30,000.

The partisans engaged in guerrilla warfare and sabotage against the Nazi occupation, instigated ghetto uprisings, and freed prisoners. In Lithuania alone, they killed approximately 3,000 German soldiers. They sometimes had contacts within the ghettos, camps, Judenrats, and with other resistance groups, with whom they shared military intelligence.

In Eastern Europe, many Jews joined the ranks of the Soviet partisans: throughout the war, they faced antisemitism and discrimination from the Soviets and some Jewish partisans were killed, but over time, many of the Jewish partisan groups were absorbed into the command structure of the much larger Soviet partisan movement.^{[better source needed]} Soviet partisans arrived in the western Ukraine in 1943, and consisted of Russians, Ukrainians, Poles, and Jews, and were smaller in size than units in Belarus, which was more suitable for partisan warfare. Released Soviet archive data suggest that Jews accounted for 5.2% of the partisans in Ukraine.

Jewish partisans had to overcome great odds in acquiring weapons, food, and shelter and in evading capture. They typically lived in dugouts (known in Russian as zemlyankas, землянка) in forest camps. Nazi reprisals were brutal, employing collective punishment against their supporters and the ghettos from which the partisans had escaped, and often using "anti-partisan operations" as pretexts for the extermination of Jews. In some areas, Jewish partisans received support from villagers, but due to widespread antisemitism and fear of reprisal, the Jewish partisans were often on their own. The farmers were struggling to supply all the different forces which were demanding food, at times leading to conflict. As Allan Levine noted, "That Jewish partisans and fugitives were guilty of stealing food from Polish farmers is an uncontested fact. It happened regularly.", but at the same time notes that such robberies were their only choice other than starvation.

The food situation varied between units, while some faced starvation, others were well supplied and sent their food stocks to Soviet Union. In order to survive, Jews had to put aside traditional dietary restrictions. While friendly peasants provided food, in some cases food was stolen from shops, farms or raided from caches meant for German soldiers. As the war progressed, the Soviet government occasionally airdropped ammunition, counterfeit money and food supplies to partisan groups known to be friendly.

Those who managed to flee the ghettos and camps had nothing more than the clothes on their backs, and their possessions often were reduced to rags through constant wear. Clothes and shoes were a scarce commodity. German uniforms were highly prized trophies: they were warm and served as disguises for future missions.

Those who were wounded or maimed or fell ill often did not survive due to the lack of medical help or supplies. Most partisan groups had no physician and treated the wounded themselves, turning to village doctors only as a last resort.