Abstract: Application 311-B twice regression D- the best design, mung beans were tested with N、P and K Applying model of mung beans were studied . From the model , result of the amount of applying fertilizer of the optimization 1hm2 land were applied with 48.88kg carbamide ; 164.85kg calcium superphosphate; 64.43kg potassium sulphate, the yield reached 1321.85kg/hm2. Efficiency of single fact and their interaction were analyzed, While effect of fertilizer on high of individual plant and stem-thick and weight of thousand grain were analyzed.