The operating income of commercial banks mainly includes traditional spread income (net interest income), net fee and commission income (also known as intermediary business income) and others. Other operating income mainly includes investment income, gains and losses from changes in fair value, summary gains and losses and other business income. Strictly speaking, intermediary business is a unique name in China, and it is an imported product. In practice, some people call it off-balance sheet business, while others classify it as intermediate business.

On the basis of asset business and liability business, commercial banks make use of the advantages of technology, information, institutional network, capital and reputation, and act as intermediaries and agents to handle entrusted matters such as payment, consultation, agency, guarantee and lease for customers, provide various financial services and charge a certain fee. In two traditional businesses, asset business and liability business, banks participate as a party to credit activities; Intermediate business is different. Banks no longer directly act as a party to credit activities, but only play the role of intermediary or agent, and usually implement paid services. In a broad sense, the intermediary business of commercial banks refers to the business that does not constitute the assets and liabilities of commercial banks on the balance sheet, but forms the non-interest income of banks.

The most common basis for the classification of intermediary business types in the world is the income source standard. According to the source of income, the American banking industry divides intermediary business into the following five categories: first, trust business refers to the transaction and service income generated by the trust department; The second is investment banking and trading business, which refers to the income generated by securities underwriting and financial trading activities; Third, deposit account service business, including account maintenance; Fourth, fee income, including credit card fee, loan securitization, mortgage refinancing service fee, mutual fund and annuity sales, ATM withdrawal fee, etc. Fifth, other fee income, including data processing service fee and income from selling various assets. Payment and settlement intermediary business refers to check settlement, import bill of lading, acceptance bills, etc., which are related to monetary payment and fund transfer caused by creditor's rights and debts. A bank draft is a bill issued by an issuing bank and unconditionally paid to the payee or holder according to the actual settlement amount at sight. A commercial bill is a bill issued by the drawer and entrusted by the payer to unconditionally pay a certain amount to the payee or holder on a specified date. Commercial bills are divided into bank acceptance bills and commercial acceptance bills.