The article examines the mechanism of administrative and legal regulation of medical and social expertise, its concept and essence are clarified. The structure and mechanism of administrative and legal regulation of medical and social expertise is defined, its general (main) elements are characterized, which include: 1) administrative and legal norms; 2) administrative and legal relations; 3) acts of application and implementation of administrative and legal norms. It has been updated that the mechanism of administrative and legal regulation, including MSE, is a means of practical implementation of the regulatory influence of public administration subjects on social relations and, at the same time, a complex phenomenon that deserves the attention of representatives of the scientific and legal community. It is indicated that the main legislative act in the MSE system is the Law of Ukraine «On the Rehabilitation of Persons with Disabilities in Ukraineя» dated 06.10.2005 No. 2961-IV, which provides for the definition of the concept of «medical and social examination» (Article 1) and generally regulates the procedure for organizing and conducting the International Trade Fair (Article 7). It has been updated that the mechanism of administrative and legal regulation, including MSE, is a means of practical implementation of the regulatory influence of public administration subjects on social relations and, at the same time, a complex phenomenon that deserves the attention of representatives of the scientific and legal community. It is indicated that the main legislative act in the MSE system is the Law of Ukraine «On the Rehabilitation of Persons with Disabilities in Ukraine» dated 06.10.2005 No. 2961-IV, which provides for the definition of the concept of «medical and social examination» (Article 1) and generally regulates the procedure for organizing and conducting the International Trade Fair (Article 7). Attention is focused on the rule-making activity of a specialized subject of public administration – the Ministry of Health of Ukraine, which carries out legal regulation of MSE by issuing special orders, as an example of the order «On approval of the forms of the individual rehabilitation program of a disabled person, a disabled child and the procedure for their preparation» dated October 8, 2007 No. 623, «On the approval of the Instructions on establishing disability groups» dated September 5, 2011, No. 561, «On the approval of the Procedure and Criteria for establishing by medical and social expert commissions the degree of permanent loss of professional capacity as a percentage for employees who have suffered health damage, related to the performance of labor duties» dated 06/05/2012 No. 420, «On approval of forms of primary accounting documentation used in medical and social expert commissions» dated 07/30/2012 No. 577. It is proposed to divide administrative and legal norms as the main element of the mechanism of administrative and legal regulation of medical and social expertise into basic and special (concretizing) ones, and subjects of public administration as a mandatory party of administrative and legal relations that are formed on the occasion of providing (receiving) of medical and social expert services, - to subjects of public-authority powers and subjects of public-service (non-authority) powers.