A field experiment with potato of Zhuang 3 was carried out to study the effects of different N，P2O5，K2O rates on yield，water and fertilizer using efficiency in dryland of Ningnan.The results showed that potato yield showed a parabola increasing with the increase of nitrogen，phosphorus and potassium fertilizer.The increasing range was the highest with nitrogen，and followed by phosphate fertilizer.The increasing by potash fertilizer was minimum and not significant with the control.Nitrogen application had significant influence on the yield component factors.Potassium application was helpful for tuber bulking.Nitrogen，phosphorus and potassium nutrient accumulations of potato were increased with higher fertilizer applied rates.Nitrogen， phosphorus fertilizer use efficiencies of potato were increased firstly and then decreased with fertilizer applied rates increasing.Potassium fertilizer use efficiency was decreased with fertilizer applied rates increasing.The partial factor productivity of nitrogen，phosphorus and potassium fertilizer on potato was significantly decreased （P<0.05） with higher fertilizer applied rates.The water use efficiency(WUE) of potato was significantly increased with apply of N,P,K fertilizer，but the WUE decreased when nitrogenous fertilizer was higher than 240 kg/hm2 and potassium fertilizer was higher than 135 kg/hm2.The WUEs of N,P,K fertilizers was increased by 19.6%～31.2%,11.2%～12.6%,1.3%～9.5% respectively.For best economic benefit and higher WUE，the recommanded N，P2O5 and K2O rate for potato in dryland of Ningnan were ranged from 174.0～189.7 kg/hm2,92.2～94.6 kg/hm2,113.0～113.7 kg/hm2，respectively.