In this paper, the fluid governing equations were discretized based on the Finite Volume Method (FVM), and then the three-dimensional fluid-solid coupling calculation was performed with the Discrete Element Method (DEM). First, the appropriate control equations were selected for the porous media, including the motion equation for fluid, the motion equation for particle and the fluid-solid interaction equation. Then the compiled program of Computational Fluid Dynamics (CFD) was introduced into the DEM for coupling computation. Finally, the numerical simulation of the single particle sedimentation was performed. The results showed that: when the particle began to fall, the speed increased rapidly, then the increasing rate gradually slowed down and the speed gradually became stable; as the particle descended, the drag force increased rapidly and gradually coincidd with the floating gravity; after the particle speed was stable, the water pressure (deducting the hydrostatic pressure)was a butterfly-shaped distribution near the particle, and the negative pressure rised above the particle and the positive pressure appears below it; the water below the particle flowed downward to both sides while the water above the particle converged toward the upper portion of the particle. The results showed that the compiled CFD programs coupled well with the DEM, and can be used to study the fluid-solid coupling problems of porous media.