The concentration of financial institutions improves the cooperation efficiency of different types of financial institutions， accelerates the speed of capital flows，promotes the adjustment of industrial structure， and further the economic growth. Because of the close communications between provincial economic activities， the provincial financial agglomeration has a spillover effect on the growth of regional economic.On the index calculation，the method of comprehensive evaluation is used to draw the financial agglomeration index in this paper.By adopting spatial econometric model，we have an empirical analysis of the impact of financial agglomeration on economic growth in five provinces of Northwest China.The result shows that the financial agglomeration has a significant positive spillover effect on economic growth.The introduced control variable“government investment”also has the obvious influence function on the economic growth.Therefore，the effective use of spatial spillover effect of financial agglomeration requires the government to give macro policy support and actively promote regional financial exchanges and cooperation and the formation of regional financial center.