Auditing can be investigated from different angles, thus making different classifications. According to different audit subjects, audit can be divided into national audit, department and unit audit and social audit.

1. National audit

National audit generally refers to the audit carried out by the state organization, specifically the audit conducted by the audit institution specially established by the state. Audits organized and implemented by the State Council Audit Office and its dispatched offices and audit offices (bureaus) of local people's governments at all levels belong to national audits. China's national audit institutions exercise audit supervision power on behalf of the government and independently exercise audit supervision power according to law. The National Audit Office has the right to audit and supervise the implementation of the central budget, and local audit institutions at all levels have the right to audit and supervise the implementation of the budget at the corresponding level; The Audit Commission supervises the financial revenue and expenditure of the central bank through auditing, and the auditing organ has the right to supervise the assets, liabilities, profits and losses of state-owned financial institutions and enterprises with state-owned assets holding or leading position, the implementation and final accounts of national construction projects, the financial revenue and expenditure of social security funds, social donation funds and other relevant funds and funds, and the financial revenue and expenditure of international organizations and foreign government aid and loan projects; Audit institutions also have the right to conduct special audit investigations to relevant localities, departments and units on specific matters related to national fiscal revenue and expenditure. State audit institutions also have the right to request the submission of information, the right to supervise and inspect, the right to investigate and collect evidence, the right to suggest the correction of relevant regulations, the right to inform the relevant departments or announce the audit results to the public, the right to deal with the economy, the right to punish, and the right to suggest that the responsible personnel be given administrative sanctions and some administrative compulsory measures. At the same time, national audit institutions can also conduct authorized audits and entrusted audits.

2. Audit of departments and units

Refers to the audit carried out by the full-time audit institutions within the department and the unit within the system and the unit. This kind of audit belongs to internal audit, and its audit institution is independent of the accounting department, directly accepting the leadership of the highest person in charge of the department and reporting to it. The main purpose of department and unit audit is to check mistakes and prevent malpractices, improve management, and thus improve management quality, work efficiency and economic benefits. The audit of departments and units involves a wide range, and its audit methods are also flexible, generally according to the needs of departments and units management. This kind of audit can be further divided into departmental audit and unit audit.

Departmental audit refers to the audit supervision of the financial revenue and expenditure and economic activities of the department and its subordinate units by the audit institutions or full-time auditors of government departments or competent departments of enterprises. The main task of departmental audit is to supervise the implementation of national guidelines, policies, laws, regulations and departmental system provisions according to the needs of the work of the department under the premise of implementing the tasks specified by the national auditing organ and the superior competent department; Organize regular or irregular financial revenue and expenditure and economic accounting quality audit, maintain financial law and discipline, improve accounting quality and improve rules and regulations; Regularly carry out economic benefit audits, organize experience exchanges, sum up lessons, and promote the improvement of economic benefits of this system; In view of the tendentious problems commonly existing in management, conduct simultaneous audits in the industry, conduct comprehensive research according to the audited problems, and put forward improvement measures; Correctly organize and guide the internal audit work of subordinate units. Department audit has the characteristics of strong industry, strong pertinence, flexibility and timeliness. For example, department audit can organize synchronous audit, mutual audit, counterpart audit, key or special audit according to the characteristics and needs of the system, so as to know the operation status of the system in time, and take necessary measures to correct mistakes and improve operations as needed and possible. Unit audit is an audit of economic activities within the scope of enterprises and institutions by audit institutions or full-time auditors.

3. Social audit

Refers to the independent audit conducted by social certified public accountants. The social audit organizations in China are mainly accounting firms. Accounting firms mainly provide financial audit and management consulting services for overseas enterprises, horizontal joint ventures, collectively-owned enterprises and individual enterprises; Entrusted by state audit institutions, other government departments, competent departments of enterprises, enterprises and institutions, it handles the identification of economic cases, tax declaration, capital verification, feasibility study, dissolution and liquidation, financial revenue and expenditure, economic benefits and economic responsibilities audit.