The application of economic-mathematical modelling in the system of enterprise knowledge management The features of various approaches to the economic and mathematical modeling of knowledge management processes at the enterprise are explored. The essence of the matrix model of information structuring lies in the fact that there are separate blocks of information that need to be learned to obtain professional knowledge, and which are formalized in the form of a matrix. In the process of managing the level of professional knowledge, it is necessary to form a corresponding appropriate level of knowledge for each information block in the form of a matrix. The deviation matrix reflects weaknesses in the employee’s professional knowledge and allows to establish the necessary training directions for the employee (information blocks that have test results below the required level). This is the matrix for making managerial decisions in matters of raising the level of professional knowledge of an employee to the required level. The fuzzy predictive model for assessing the level of knowledge uses a chain of question and answer structures of a nontrivial type. As the main data, a lot of answers are used, many questions, the relationship of which determines the fuzzy relation that characterizes the correct answers to the questions from the multiplicity of these answers. The model for optimizing the structure of the knowledge management system makes it possible to create an optimal structure of the knowledge management system with information on the impact of its components on improving the efficiency of the company’s operations. The application of the theory of games in the enterprise knowledge management system allows you to simulate the strategies of the participants in the game and determine the most optimal state for each of the situations, contributes to the construction and use of the most effective motivational mechanisms in each individual case. Therefore, the mechanisms of game theory can be used to create systems for motivating staff to share knowledge. The knowledge management system with the use of the network modeling tool - the cognitive map is considered. The cognitive map of knowledge management consists of three components: the knowledge base, the external environment and the internal environment. Each of the approaches has advantages and disadvantages, however, for the management of enterprise knowledge, a complex combination of different approaches to economic and mathematical modeling is required, which will avoid the shortcomings of each individual approach.