Article 22 of China's "Commercial Bank Law" stipulates: "Commercial banks implement a financial system of unified accounting, unified allocation of funds and hierarchical management for their branches. Branches of commercial banks do not have legal person status and conduct business according to law within the scope authorized by the head office, and their civil liabilities shall be borne by the head office. " Because the branches of commercial banks are often all over the country or even all over the world, and the environment in which each branch is located is very different, if every loan business is approved by the head office regardless of the amount, it will inevitably affect efficiency. In order to effectively carry out financial business, the head office of a commercial bank must manage and authorize its branches at different levels, which is reflected in the loan business, that is, the loan grading approval system. Accordingly, the loan grading approval system is a system established by commercial banks as legal persons for their branches according to law, which is only applicable to the internal relations of legal persons, but not to the external relations of legal persons.