Underwater full pile casing rock-socketed cast-in-place pile construction method

The invention discloses a construction method of an underwater full pile casing rock-socketed cast-in-place pile. Positioning a rotary drilling construction ship; according to the pile testing result, the rotary drilling construction ship is positioned through eight-anchor positioning; performing underwater rock surface treatment: performing drilling construction at eight anchor positions by using a drill rod according to terrains, and performing drilling at least twice in an abrupt slope area by using a step drilling method; a steel casing is installed, specifically, the steel casing is hoisted to penetrate through the guide frame to be installed to the designed position, and the steel casing is temporarily fixed through a wedge-shaped limiting stopper; pile stabilizing concrete is poured, specifically, concrete is poured underwater through a guide pipe between the steel casing and the hole wall, and the wedge-shaped limiting stopper is pulled out; after the water level rises to the set position of the steel