Since the heat exchanger plates are designed along vertical direction, the uniform level of the inlet medium has vital effect on the whole efficiency of cooling rate. The multi-holes distributor optimum design was discussed.The structure design of multi-holes distributor was put forward and the design method was mathematically described ,then deduced the formula of pressure reduction. Flow pattern in the distributor was simulated by CFX software. The results show that the effect of uniform distribution is good. These have some importance to fundamental thought of distributer optimum design and formular reduction of pressure on the distributor design.