Tosia Altman (Hebrew: טוסיה אלטמן) (24 August 1919 – 26 May 1943) was a courier and smuggler for Hashomer Hatzair and the Jewish Combat Organization (ŻOB) during the German occupation of Poland and the Warsaw Ghetto Uprising.

Born into a well-off family of Zionist leanings, she joined Hashomer Hatzair and became part of the central leadership before the war. After the invasion of Poland, she fled with the leadership of the youth movements to Vilnius. Volunteering as a courier, she passed herself off as a Polish gentile and risked her life to visit ghettos, first to organize underground education and later to warn them of the impending mass extermination of Jews.

After the formation of the ŻOB in the Warsaw Ghetto, Altman was appointed a liaison to the Home Army. She smuggled weapons and explosives into the ghetto and established a chapter of the ŻOB in the Kraków Ghetto. During the Warsaw Ghetto Uprising, she acted as a courier between bunkers. Seeking shelter at the command bunker at 18 Miła Street, she was one of six to escape when the Germans discovered it. Despite suffering wounds to the leg and head, Altman escaped from the ghetto via the sewers. She was captured two weeks later when the factory she was sheltering in caught fire. Severely burned, she was handed over to the Gestapo and died two days later.