General elections were held in South Africa on 20 October 1915 to elect the 130 members of the House of Assembly. This was the second Union Parliament. The governing South African Party (SAP) of General Louis Botha emerged from the elections as the largest party, but did not receive an overall majority.

The House of Assembly was the lower house of the Parliament of South Africa from 1910 to 1981, the sole parliamentary chamber between 1981 and 1984, and latterly the white representative house of the Tricameral Parliament from 1984 to 1994, when it was replaced by the current National Assembly. Throughout its history, it was exclusively constituted of white members who were elected to office predominantly by white citizens, though until 1960 and 1970, respectively, some Black Africans and Coloureds in the Cape Province voted under a restricted form of suffrage.