Abstract: This paper deeply analyzes the temporal and spatial distribution of social expenditure in China through convergence model and decoupling index. It is found that in the process of welfare expansion, China's social expenditure has an absolute (conditional) convergence trend, but there are differences in various regions and types of social expenditure. Among them, the convergence speed in the western region is the fastest, followed by the middle, and the eastern region is the slowest; The convergence rate of household survey expenditure is faster than that of social insurance expenditure and inclusive expenditure, and the convergence rate of social protection project expenditure is faster than that of education expenditure. In addition, the dynamic relationship between social expenditure and economic growth focuses on expansion connection, relatively negative decoupling of expansion and relatively decoupling of expansion. The development trend of social insurance expenditure and economic growth remains relatively stable, while the decoupling degree of household survey and inclusive expenditure from economic growth is more obvious, which is affected by "top-by-top competition", The decoupling ratio between education expenditure and economic growth is significantly higher than that between social protection expenditure and economic growth. In the future, China should reasonably plan the spatial layout of people's livelihood security resources, actively allocate welfare resources according to population factors, and strive to realize the common vision of an all-round well-off society.

Key words: welfare expansion, social expenditure, livelihood security, spatial convergence, decoupling