In this paper, a numerical investigation of the impact of the longitudinal position of the center of buoyancy and the prismatic coefficient on the total resistance of the passenger ship is carried out using the software package STAR - CCM+ for computational fluid dynamics. Hull form modification is performed with the software package CAESES. The unsteady flow of a viscous fluid is modeled by the Reynolds averaged Navier–Stokes (RANS) equations, which are discretized by the finite volume method. The k-ω SST turbulence model is applied, and the position of the free surface is determined by the volume of fluid method. The limitations of the longitudinal position of the center of buoyancy are defined by the company Flow Ship Design d.o.o., and the limitations of the prismatic coefficient are determined according to Lackenby method for the hull form modification. The verification study is carried out and the total numerical uncertainty of the total resistance, sinkage, and trim angle of the initial hull form of the passenger ship is calculated. A detailed analysis of the flow around the ship hull is carried out, which includes the determination of the wave pattern, free surface position, hydrodynamic pressure distribution, and tangential stresses distribution along the ship hull. Finally, a comparison of the obtained values of total resistance, sinkage, and trim angle for all modified hull forms is given. It was concluded that by shifting the longitudinal position of the center of buoyancy by 0.4 % Lpp, it is possible to achieve a reduction in the total resistance of 2.11 % compared to the total resistance of the initial hull form. In addition, by increasing the prismatic coefficient by 5 %, while maintaining a constant draft and the longitudinal position of the center of buoyancy, resulting in an increase in the displacement volume by 4.96 %, it is possible to achieve a reduction in the total resistance of 1.43 %. To determine the resistance curve, numerical simulations of the resistance test are carried out for two additional speeds for the most favorable hull form from the total resistance point of view. The results of the conducted research pointed out that even by simple modifications of the hull form, it is possible to achieve a reduction in the total resistance of the ship without the need to apply complex optimization algorithms.