The article examines aspects of current Ukrainian legislation, including regulations of the Antimonopoly Committee of Ukraine on concentration of business entities. The author analyses and compares them, and as a result reveals the legal mechanisms of state control over concentration processes of business entities, which consist in granting permission or prohibition of concentration by the controlling authority. The cases in which concentration is subject to a thorough examination by the supervisory authority and can be carried out only with its consent, as well as cases in which such consent is not required, are considered. The article describes the procedure for business entities to apply to the Antimonopoly Committee of Ukraine with an application for a merger clearance, and also highlights the requirements that must be met by the applicant in such an application for its consideration by the supervisory authority. The article outlines the process of consideration of cases by the Antimonopoly Committee of Ukraine on granting permits to business entities for economic concentration. The rights and obligations of applicants, third parties, interested parties and the supervisory authority during the consideration of cases are described. The list of decisions made by the committee based on the results of consideration of applications, as well as the grounds for their adoption, is considered. The author clarifies the main principles of appealing against such decisions in court or by appealing to the Cabinet of Ministers of Ukraine. The author examines the criteria and types of liability for conducting concentration without obtaining a permit, as well as for providing false information to the controlling authority in the process of obtaining a permit for concentration actions. The article examines the positive and negative factors of the State’s competition policy and legal support for control over concentration processes. The author identifies specific aspects that may have a positive impact on the effective reform of Ukrainian competition law and, as a result, ensure that Ukraine pursues an effective competition policy in the field of control over economic concentrations, which will lead to the prosperity of competition as a driving force for economic and social progress.