Fluid simulation plays an important role in movie special effects, computer games, etc. In recent years, the Smoothed Particle Hydrodynamics (SPH) has become a popular fluid simulation method due to its simpler implementation and better processing capabilities for various complex scenes. Although the computational efficiency of the current SPH method has been significantly improved, there is still much room for improvement in pressure solving. This paper proposes an improved pressure solution method based on DFSPH. Firstly, we eliminate the velocity divergence of the fluid by changing the solution order of the nonpressure force and divergence solvers, thereby reducing the number of iterations required by the density solver. Secondly, the SOR method is applied to the pressure solver, furthering reducing the number of iterations of the density solver. Various experiments demonstrated that our method improves the efficiency of the solver with little decrease in stability compared to state-of-the-art methods. The speedup factor reaches between 1.35 and 1.4 at a time step of 5ms, and the more the number of particles, the faster the performance increases.