Abstract: As an important part of the social security system, social assistance plays a fundamental role in the realization of social fairness and justice. A scientific and reasonable division of the financial expenditure responsibilities is a necessary financial guarantee for the sound operation of the social assistance system. Based on the“Barrow Rule”and the Cobb-Douglas function model derivation, this paper makes use of the regression analysis method to calculate the optimal fiscal expenditure responsibility for social assistance in China. It also studies the adjustment and optimization of the expenditure responsibilities for social assistance from the different perspectives, such as the deviation of expenditure responsibility and the financial burden of social assistance, etc.. The findings show that the level of the expenditure responsibilities for social assistance of the central government continues to tend to be optimal, and the eastern region exceeds more, thus it is possible to moderately reduce the financial expenditure responsibilities for social assistance of the central government in the eastern region, and the reduced part can be transferred to the central and western regions where the financial burden and social assistance tasks are heavier. The social assistance expenditure responsibilities at the provincial finance level are constantly approaching optimization, but none of them have reached the optimal level; the negative deviation of the expenditure responsibilities in central and western regions is relatively larger, it is necessary to appropriately increase the social assistance expenditure responsibilities of the provincial finance. The level of the fiscal expenditure responsibilities for social assistance at the county (district) level has exceeded the optimal level, especially in the central and western regions.

Key words: social assistance, fiscal expenditure, expenditure responsibility