In order to explore the best ratio of nitrogen，phosphorus and potassium under drip irrigation for sugar beet in arid area，KWS 9147 was used as material and “3414” experimental design was used to analyze the effect of the ratio of nitrogen，phosphorus and potassium on the economic yield of sugar beet. The results showed that different fertilization ratios had significant effects on beet root yield，sugar content and sugar yield. The single effect order of fertilization factors on sugar beet root yield was nitrogen fertilizer > potassium fertilizer > phosphorus fertilizer；The order of individual effects on sugar content and sugar yield was phosphorus fertilizer > nitrogen fertilizer > potassium fertilizer. In this experiment，applying sufficient nitrogen and phosphorus fertilizer was beneficial to improve the yield of sugar beet. When the application amount of potassium fertilizer(K2O)was more than 46.74 kg·hm-2，the yield was decreased，when the application amount was more than 72.79 kg·hm-2，the sugar yield was decreased，and when the application amount of phosphorus fertilizer(P2O5)was more than 35.91 kg·hm-2，the sugar content of root was decreased. In the range of N 0～39.1 kg·hm-2 and P2O5 0 ～ 89.5 kg·hm-2，the sugar yield of sugar beet root was increased significantly with the increase of fertilizer application level. The interaction of nitrogen and phosphorus，phosphorus and potassium，nitrogen and potassium fertilizers effectively improved the sugar content of root. In this experiment，when the ratio of N∶P2O5∶K2O was 2.7∶1∶1.1，the highest sugar yield(26772.1 kg·hm-2)could be obtained.