Shmuel Dayan (8 August 1891 – 11 August 1968) was a Zionist activist during the British Mandate of Palestine and an Israeli politician who served in the first three Knessets.

Born in the town of Jashkov in the Ukraine, he joined the Zionist movement as a boy and emigrated to Palestine, then under Ottoman rule in 1908. He worked in agriculture in the settlements of Petah-Tikva, Rehovot, Yavne, and Kinneret until 1911, when he became active in the Young Workers Party.

He was also one of the earliest settlers in Deganiah, the country's first kibbutz, though he left in 1921 to help establish the moshav of Nahalal.

As one of the leaders of the nascent Moshav Movement, he made several trips to the United States and Poland as a Zionist emissary.

In 1949, he was elected to the First Knesset for the Mapai party, and served as Deputy Speaker of the Knesset. He continued as a member of the next two Knessets, until 1955.

Shmuel Dayan was the father of Israeli general and politician Moshe Dayan and the grandfather of politician Yael Dayan and director Asi Dayan.