Abstract: In order to understand effect of controlled release urea（CRU） on potato, this paper has studied that the CRU was applied to potato in Wuchuan county and Chayouzhong banner in 2009—2011, where is main production of potato. The results indicated that yield of the potato was increased significantly by applying nitrogen fertilizer, CRU production of potato increased by 5.7% ~ 12.7% than conventional urea, an average of 7.4%, and the yield was the biggest by combined use of controlled release urea with conventional urea. CRU compared with conventional urea, Commodity potato rate increased 2%,tuber number per plant increased 0.2 ~ 0.6, tuber weight increased 6.5~7.2 g. The agronomic efficiency of nitrogen fertilizer was improved 7.5~8.8 kg/kg N by CRU application, and nitrogen use efficiency（NUE）was increased by 11.4%~15.9%. So it can significantly improve nitrogen fertilizer effect and reduce nitrogen loss. Two fertilizer effect was almost the same both75% CRU and 100% conventional urea in one base,which showed CRU can reduce the nitrogen application by 25%, under background of scarcely production cut.