The aim of the study is substantiation of the main aspects of the water economy complex management structure improvement by the introduction of the state and private partnership principles in the water economy system. The existent Ukrainian system of the water resources management is economically costly and has the unfavourable and unbalanced mechanism of distribution, protection and restoration of the water resources quality, from the point of view of the organizational management structure. The analysis of the existent experience in the field of water resources management in different countries of the world has proved that one of the most appropriate and efficient forms of the state and private partnership realization in the field of water economy of Ukraine are water consumers associations. However, taking into account the international experience, we conclude, that the main conditions of the state and private partnership introduction are determination of the state government agencies role in the irrigation systems and infrastructure management in the country, transfer of the state irrigation network,drainage and infrastructure objects to the water users associations, development of the legislative and methodological support to form associations, and whereas a non-profit position of the associations in the legislative system of the country is quite important, it should be clearly and exactly determined by the legislation. Improvement of the management system by the introduction of the state and private partnership in the water economy complex of Ukraine is impossible without substantiation of the main stages in modernization and renovation of the branch activity. An important condition of the process is gradual and tolerant share of the water resources management functions and water economy and melioration systems exploration between the State agency of water resources of Ukraine, regional management bodies and water users associations at the basis of the state and private partnership principles.