The effective operation of the enterprise depends of the rational use of all resources, which necessitates the transition to the optimal cost management system. The relevance and high social economic importance of cost management problems predetermines the need of deep study and determine the optimal cost structure. The article deals with the problem of imperfection of modern methodical approaches to cost accounting. The purpose of the article is to highlight the modern order of cost accounting, organizing theoretical and practical recommendations for optimizing the costs of the enterprise in market conditions. General scientific and special methods of investigation, analysis and synthesis, comparison, generalization and grouping expenses and regression and correlation analysis for predicting the dynamics of costs have been used in the study. Methodological basis of cost management has been justified and directions to optimize their structures allowing use resources of the enterprise efficiently, reduce production costs and maximize profits have been set. The content has been defined, advantages and disadvantages of these methods of optimization the absolute value of the cost of the entity as ABC analysis; ХУZ analysis; cost analysis have been justified. The conditions of their use on Ukrainian enterprises have been determined. The practical significance of the study is to clarify the characteristics of the basic cost accounting system, the results of which will allow to draw conclusions about the possibility of their use. The comparative analysis of these methods of determining cost has been conducted: standard costing; direct costing; target costing; kaizen costing; ABC-costing; Theory of constraints. Further research in cost management regard the development of a balanced system of planning, forecasting, and control over the entire business process chain where critical evaluation not only of industrial and financial assets, but also intangible assets (brand, customer loyalty, the number of regular customers) and competitive advantage («know-how» innovation management, etc.) technology to improve efficiency and achieve the desired results in different directions.