When writing this scientific article, the author considered the role of internal audit in the economic security of credit institutions. The formed conditions of instability of the economic system and negative external impact, manifested in sanctions pressure, mediate the need to increase the effectiveness of internal audit in credit institutions in order to increase the economic security of an economic entity. The author considers the definition of internal audit in accordance with the legislation of the Russian Federation, identifies the tasks of internal audit, as well as the prerequisites for the formation of an internal audit service in an organization, and the main functions of internal audit. Internal audit is an independent and objective activity of providing guarantees and consulting, which improves the activities of the organization and increases its value. The differences between internal audit and other forms of control are highlighted. It is important to note that internal audit occupies one of the most important roles in the structure of the organization and is in constant interaction with the system of economic security of the organization. Internal audit is considered the foundation of the organization and is considered as a key element for the application of the accounting system. Effective internal audit planning allows audit activities to be one of the aspects that protects the organization and increases economic security. Moreover, effective internal audit planning and prioritization of the units to be audited are important both from the point of view of the effective use of internal auditors and from the point of view of the effective use of economic resources. Thus, the tasks assigned to the study can be considered completed. The problems of the research topic were fully developed, a block of relevant information was presented and analyzed for each of the tasks, and appropriate conclusions were drawn.