Three backgrounds, including the new normal of economic growth shifted into medium-to-high in speed, the heavy burden to urban employees for health expenditure, and targeted administration to basic medical insurance of urban employee (BMIUE) , made that calculation to appropriate premium rate scientifically is the most important content for promoting the reform to BMIUE in the period of the 13th Five-year Plan. The paper developed a dynamic model on determining the appropriate premium rate for BMIUE. The results of calculation showed that in the period of the 13th Five-year Plan, if keeping the current financial institutional arrangement named individual account and social pooling constant, the current premium rate for BMIUE can be cut from 8% into 7.9%. If cancelling individual account and letting financial institutional arrangement be pay-as-you-go system of social pooling completely, the current premium rate for BMIUE can be cut from 8% into 7%.