The efficiency of social security system shows not only in system's construction, but also in system's implementation. This article uses the data envelope analysis method to compare the 30 provinces and cities' (except Tibet) efficiency of fiscal expenditure on social security. The results show the local economic development level has effect on the efficiency and the efficiencies in different provinces are rather different. The efficiencies of Anhui and Hunan Provinces are the lowest. According to four big economic plate division, the efficiencies of the Northeast three provinces are the highest, the efficiency of the Middle area is the lowest; According to eight big economic zone division, the efficiencies of the Northeast, the Eastern coast, and the South coastal provincial are the highest, the efficiency of the Yangtze River middle reaches area is the lowest; If the inefficient provinces want to maintain the security amount of present situation, the money can be saved about 27.8%, 24.3%, 23.2%, 19%, which includes death and the social welfare relief payments, public sector retirement employee's pension, and the social security subsidy, as well as social security and social welfare sector employees' wage.