The Sai Kung Peninsula is a peninsula in the easternmost part of the New Territories in Hong Kong. Its name comes from Sai Kung Town in the central southern area of the peninsula. The southern part of the peninsula is administered by Sai Kung District, the north by Tai Po District and the northwest by Sha Tin District.

Sai Kung Town, or simply Sai Kung, is a town on the Sai Kung Peninsula facing Sai Kung Hoi in the New Territories, Hong Kong. Sai Kung is the central hub of nearby surrounding villages, and, hence the name, may also refer to the areas in its immediate surroundings.