The karst areas distribute widely in south China,where karsts caves form easily and the geologic condition is unfavorable for the construction of the wharf.Based on the practical project,we demonstrate the technological feasibility for the construction of gravity quay under this kind of geologic condition by special methods including the single-beam-model and the Protodyakonov’s theory,and put forward suggestions for the initial stage work such as geologic survey,which may serve as reference for similar projects.