Abstract: The relevance of the research topic is due to the fact that the activity of the authorities is to make management decisions in the framework of the implementation of their powers. The introduction of a document management and records management system is one of the priority tasks of the authorities, the successful implementation of which will allow for a transition to a higher quality level of their functioning.The effectiveness of this process is determined by the workflow and workflow system, which is the object of modeling. The purpose of the study is to develop a mathematical model for assessing the effectiveness of the implementation of an electronic document management and workflow system in government to improve performance. The results of the study were obtained on the basis of the use of the theory of system analysis, set theory, graphical models, and the model of system dynamics. The scientific novelty is connected with the development of a model for evaluating the effectiveness of introducing an electronic document management and workflow system in government for simulation modeling and forecasting of their main indicators.The main conclusions of the study are that the authors considered the construction of a mathematical model for evaluating the effectiveness of introducing an electronic document management system and office work in government using the Forrester system dynamics method. The developed model is written in the form of a system of differential equations and presented in the form of a Cauchy problem. According to the results of the study, it was found that the fourth order Runge-Kutta method is appropriate for solving this system, since, despite the increase in the volume of calculations, the fourth order method has an advantage over the first and second order methods, since it provides a small local error, which allows you to increase the step of integration and, consequently, reduce the calculation time.