Sarah Aaronsohn (1890—1917), was a member of Nili, a Jewish ring of spies working for the British in World War I. She was born and died in Zichron Yaakov in what was then known as Palestine, part of the Turkish Ottoman Empire. Israelis often refer to her as the "heroine of Nili."

Sarah lived briefly in Constantinople until she returned home to Zichron Yaakov (1915) to escape an unhappy marriage. In her travels she witnessed genocidal acts by the Turks against the Armenians, which caused her to consider the possibility that the Jewish minority in Palestine might have the same fate. This experience stimulated the forming of the Nili ring (founded in 1915 by her brother Aaron and their friend Avshalom Feinberg ).

Sarah oversaw operations of the spy-ring and passed information to British agents offshore. During the periods when Aaron Aaronsohn was abroad, she headed the spying operations in Palestine. Sometimes she travelled widely through Ottoman territory collecting information useful to the British, and brought it directly to them in Egypt. In 1917 she was urged by her brother to remain in the British-controlled Egypt, out of reach of the Turks, but she returned to Zichron Yaakov to continue her activities. That same autumn the Turks discovered Nili's operations, captured Sarah and tortured her for three or four days in Zichron Yaakov. Finally she shot and killed herself with a pistol concealed on the premises to avoid further torture and to protect her partners.

In her last letter, she expressed her hope that her activites in Nili would bring nearer the realization of a national home for the Jews in Palestine.