A virtual experimental study of the resistance characteristics of the suction pipe structure of a full-scale trailing suction dredger with the underwater pump has been carried out by using the numerical tank technology. It analyzes and studies the resistance characteristics of the bare and fully appended suction pipe that are varied with different inclined angles and speeds. It also analyzes the resistance components of each structure of the fully appended suction pipe. It can provide reference for the resistance prediction, evaluation of the ship propulsion power and the design optimization of the suction pipe structure.