Semaphore Park is a suburb in the Australian state of South Australia located in the west of Adelaide on the coastline of Gulf St Vincent.

The northern end of the suburb is considered to be located within the Lefevre Peninsula.

[9] Semaphore Park originally started as a private sub-division in Section 64 in the cadastral unit of the Hundred of Yatala under the names of New Liverpool and Mellor Park (named for Thomas Mellor[citation needed]).

[1] Glanville Blocks Post Office opened on 1 September 1896, was renamed Semaphore Park in 1947 and was replaced by the West Lakes Shore office in 1997.

[1] Semaphore Park is located within the federal division of Hindmarsh, the state electoral district of Lee and the local government area of the City of Charles Sturt.