The County economy is the basic unit of the national economy，and it directly affects the rise and fall of the national economy. Due to its own characteristics and limitations of the county economy，developing the county economy urgently needs support from various aspects，especially the support of the multi-level capital market. The relationship between Multi-level capital market and county economy is interactive：capital market provides effective allocation of funds and resources for the development of county economy，and the county economy provides capital market investment projects and investment returns. At present，our country is vigorously developing and perfecting the multi-level capital market system. Thus，clarifying the mechanism of the multi-level capital market to the county economy will achieve a win-win situation.