Cape St George Lighthouse, Lighthouse ruins in Jervis Bay Territory, Australia

Cape St George Lighthouse is a ruined stone tower on a clifftop about 3 km south of the southern entrance to Jervis Bay. The lighthouse was built in 1860 and remained in use until 1889; its lantern was removed and later installed in the Crookhaven Heads Light in 1904. The tower was used for target practice by the Royal Australian Navy between 1917 and 1922, leaving the ruins that stand today.

Cape St George Lighthouse was commissioned on 1 October 1860 despite objections from the Pilots Board, whose members questioned the site's visibility and the accuracy of the Millington and Dawson map. The contractor built the tower 2.5 miles north of the intended position, closer to his stone quarry. A New South Wales Select Committee later called the siting errors "very grave errors, highly censurable". It was replaced in 1899 by Point Perpendicular Light.

The ruins are managed by the Wreck Bay Aboriginal Community together with the Department of the Environment, Water, Heritage and the Arts as part of Booderee National Park. The site also preserves evidence of the first settlement on the Bherarerre Peninsula, and Harriet Parker's grave lies in the nearby Greenpatch camping area.

Access to the ruins is through Booderee National Park with marked paths and information boards along the way. Wear sturdy shoes since the ground is rough and the clifftop views are rewarding.

The contractor built the tower 2.5 miles north of the intended site because it stood closer to the quarry supplying its stone. A Select Committee later called the siting errors "very grave errors, highly censurable". The lantern was removed and reused in the Crookhaven Heads Light, built in 1904.