This study empirically analyzes the factors of financial system structure on the basis of bank-based and market-based perspectives based on panel data of 56 countries or regions from 2002 to 2017.The results show that the influencing factors of bank dominated financial system structure and market dominated financial system structure are quite different,Economic factors play a fundamental role in the depth of financial markets.A stable policy environment and a high level of governance will help expand the size ofthe financial market and the depth of market，Culture and law influence the banking system and capital market size through Regulatory action.In view of these, in the process of optimizing the structure of the financial system, we should consider the mechanisms of economy, governance, law and culture. In terms of enhancing the depth of the financial market, we should build a mutual promotion mechanism between the real economy and the financial system, and give full play to the regulatory role of culture and law.