Effects of N，P and K fertilizer on yield of black wax guard (‘Guishu No.1’) with field experiment were studied with the orthogonal design.The results showed that nitrogenous fertilizer，potassium fertilizer and the interaction of nitrogenous and potassium fertilizer had a very significant effect on yield，while phosphorus fertilizer and the interaction of phosphorus and potassium fertilizer had a significant effect on yield.The following was the sequential influence factors on yield of wax guard in an order from major to minor：potassium fertilizer＞nitrogenous fertilizer＞the interaction of nitrogenous and potassium fertilizer＞the interaction of phosphorus and potassium fertilizer＞the interaction of nitrogenous and phosphorus fertilizer＞phosphorus fertilizer.In this paper，the optimum factor combinations were as follows：nitrogenous fertilizer 800 kg/hm2，phosphorus fertilizer 225 kg/hm2，potassium fertilizer 750 kg/hm2，which had the maxumun production.