In view of the limitation of the traditional design,we apply the BIM technology to the construction drawing design of triangle gate of Honglan ship lock on the Qinhuai River.The advantages of BIM technology in four aspects including the collaborative design,visualization,collision check,engineering quantity statistics and plotting are expounded.The research shows that the application of BIM technology can solve problems such as inadequate depth of cooperation among different majors,lack of intuition of 2D drawing,frequent occurrence of mistakes,omission and collision,etc.It realizes the 3D modeling of spatial structure with complex curved shape and achieves the goal of design optimization and improvement of the design quality.