The 3-D RNG k - e numerical model of turbulence flow is built with FLUENT software. The mixture motions of water and sand, in the upper direction and side direction, are calculated. The results show that, the effect of jetting in upper direction is evident compare with the jetting in the side direction, under the condition of the same pressure and speed. It's easier to start suspending for the inside earth than the outside earth. The range of down jetting is smaller than that of up jetting, but is bigger than that of side jetting. These results can offer important references for the water jetting in the pile extraction of jack-ups.