The added resistance in waves is an important component of total resistance during floating transportation of immersed tunnel elements on the sea. The added resistance was calculated by hydrodynamics simulation software AQWA based on the potential flow theory. The geometrical and physical characteristics were decided by the 3D finite element model of the element and attachment structures, then a wetted surface model of the tunnel element was established to carry out the hydrodynamic analysis. Finally, the sensitivity analysis of parameters including depth of water, towing speed, wave spectrum and characteristics was made. The numerical results suggest that the added resistance when applying the P-M spectrum is greater than the results obtained from the JONSWAP spectrum, decreases with the increase of water depth, may be related to periods and directions of waves, is proportional to the square of wave height and proportional to towing speed as well.