The structural components (main) of the diagnosis of the competitiveness of the business structure, supporting the opinion of scientists and enterprise managers, are the competitiveness of the products of the business structure, the concentration of the market in which the business structure functions, as well as the effectiveness of the functioning of the business structure under risk conditions, which includes financial-economic, production and commercial efficiency. It is also stated that information technology is an effective management tool for solving economic problems in the field of management and administration. It was determined that today a relevant and important issue is the need to form new and improve existing provisions (both theoretical and practical) regarding the effectiveness of the use of information technologies in the management of a business structure under risk conditions, with the use of mathematical modeling. In view of this, the purpose of the study is to develop an economic-mathematical model for diagnosing the effectiveness of the use of information technologies in the management of the business structure under risk conditions. Based on the results of the research, the article proposes a new economic-mathematical model, and based on it, a set of parameters, criteria and ratios are formed, which ensure the effective functioning and development of the business structure, taking into account the introduction (rational use) of information technologies in the management of the business structure under risk conditions. The basis of this model is the functional relationship between profits, the level of efficiency of the business structure and business risks. The scientific novelty of the obtained results lies in the improvement of the economic-mathematical model for diagnosing the competitiveness of a business structure, which is based on the functional relationship between profits, risks and the level of efficiency of the business structure, which is one of the structural components of diagnosing the competitiveness of a business structure. This model takes into account an expanded set of economic parameters and factors and, unlike the existing ones, it includes the function of a compromise between the level of efficiency of the business structure and business risks, taking into account the peculiarities, role and significance of the use of information technologies in the management of the business structure. This type of approach makes it possible to reduce the number of inaccurate and inadequate results in the context of optimizing methods of using information technologies for making reasonable and effective management decisions (both current and prospective) in the business structure management system under risk conditions. It is advisable to conduct further research in the direction of studying practical issues regarding the formation of a quality and effective management system of the business structure in conditions of risk and uncertainty.