The viscous effect of semi-submerged body fixing under the bow of the hybrid monohull makes it difficult to calculate the hydrodynamics of the ship, and the characters of viscous flow field of the sections have great influence on the form optimization of the hull aiming at the improvement of speedy and seakeeping performance. In this paper the hydrodynamic coefficients of the hull were calculated by means of RANS method. The influence of different turbulence models to the calculation results for hydrodynamic was discussed, and this result was compared with the one calculated by means of source/dipole mixed-distribution method and analyzed. Furthermore, the characters of viscous flow field of the sections for the different turbulence models was also discussed and the paper gave the calculation method applicable to the hydrodynamic coefficients of the hull adding the semi-submerged body by calculation. The research results were valuable to the optimization of hybrid monohulls.