The internal audit of commercial banks includes the following contents: deposit business audit, which involves the audit of corporate deposits, savings deposits and foreign exchange deposits. Mainly the audit of the implementation of deposit business policies and principles and the audit of account management and business accounting.

The loan business audit is divided into: industrial and commercial loan audit, agricultural loan audit, capital construction loan audit and foreign exchange loan audit, with emphasis on loan investment and economic benefit audit. Audit of settlement business includes audit of settlement implementation principles, audit of settlement methods, audit of inter-bank transactions and audit of international settlement.

Article 60 of the Law on Commercial Banks stipulates: "Commercial banks should establish and improve their own auditing and inspection systems for deposits, loans, settlement and bad debts."

Internal audit of commercial banks refers to the internal audit department of commercial banks according to national laws and regulations, financial policies and internal control rules and regulations.

According to modern control theory, combined with the characteristics of commercial banks' business activities, the business activities, financial activities and economic benefits of commercial banks are audited, inspected, tested and supervised to judge the legality, accuracy, integrity and effectiveness of their business activities and financial activities.