Introduction. The relevance of the study is related to the problem of increasing soil fertility. The value of soil as the main means of agricultural production in a specific economic infrastructure is determined by its fertility that is its ability to satisfy the needs of specific plants for nutrients, water, and to provide the root system of plants with air and heat. The effectiveness of increasing soil fertility depends on objective soil assessments and forecasting. Therefore, mathematical modeling for the fertility level of soils for the agricultural production is an urgent task for agroengineering studies.Aim of the Study. The study is aimed at developing a mathematical model for an integrated assessment of soil fertility levels.Materials and Methods. When conducting the study, analytical methods were used and the results obtained by various authors on this problem were summarized. The object of the study was the published results of scientific researches by the authors from other scientific institutions obtained on the problem under consideration.Results. Based on an analysis of the literature references, there was made a scientifically-based list of the most significant indicators for assessing soil fertility, which includes the content of organic matter (humus), acidity, humidity, soil porosity, presence of microorganisms and clay particles, content of mobile forms of nitrogen, phosphorus and exchangeable potassium. A mathematical model has been developed based on the criterion of maximum soil fertility, which makes it possible to assess the level of soil fertility using the proposed indicators.Discussion and Conclusion. The examples of calculations based on average and basic values of indicators with the use of the proposed mathematical model are presented. They give an idea of the most typical procedures for generating indicators and assessing the process under consideration. The value of the fertility probabilistic coefficient 1 indicates soil depletion (degradation), which will not ensure an economically sound harvest. In this case, measures must be taken to increase soil fertility. When 1, the soil is fertile and is able to supply plants with nutrients, water and air for their growth and development. The soil fertility level is an important criterion for assessing the impact of agricultural technologies on environmental safety and the environment state.