Hillel Yaffe (1864–1936) (Hebrew: הלל יפה) was a Russian Jewish physician and Zionist leader who immigrated to the Land of Israel in the First Aliyah during the Ottoman Empire.

In the early 20th century he was instrumental in curing Malaria, which at that time was the main cause for death of Jews, and helped improve the medical infrastructure of the Yishuv during the same period.

His nephew, Yigael Gluckstein who wrote under the name Tony Cliff, was a Palestinian Jewish Trotskyist and the founder of the British Socialist Workers Party.

Slowly it became apparent that a fundamental, broad program would be necessary to remove the scourge of malaria from the Jewish settlement, since individual treatment was insufficient.

Yaffe's decision to combine medicine with political activism derived from his realization that in order to fulfill his mission for the Jewish settlement in Israel, it was necessary to form new institutions.

Yaffe understood that in order to succeed in eradicating malaria, he needed to combine practical treatment of patients with research, community activism, and politics.

When Yaffe accepted this job, he moved to Jaffa, which was a central city, and managed to raise money to drain the infested swamp near Hadera.

Yaffe's extensive knowledge of the importance of public health and the practical realities of Israel led him to build a widespread system of prevention.

Yaffe had minor but crucial involvement with NILI, the Jewish espionage network centered in Zichron Ya'akov which assisted the United Kingdom in its fight against the Ottoman Empire in Palestine between 1915 and 1917, during World War I.

In Spies in Palestine,[2] James Srodes quotes the diary of Yaffe as saying that Sarah Aaronsohn, after her botched suicide attempt, as she lay suffering & fearful that she would unintentionally reveal secrets to the Turks in her delirium (which she did not), pleaded with him, "For heaven's sake, put an end to my life.

I beg you, kill me… I can't suffer any longer…" Instead, Yaffee administered a non-fatal dose of morphine, thus prolonging her life.

He began to plead with farmers to hang canopies around the beds, nets around the windows, and to clean every pool of standing water.

Forestation of large areas near Hadera with eucalyptus trees was part of Yaffe's effort to change the environment in order to respond comprehensively to the disease.