Abstract: This article makes an attempt of comprehensive analysis of the phenomenon of youth parliamentarism as a structural possibility of involvement of representatives of the  Russian youth in law-making activity. The authors formulate a definition of youth parliament, as well as describe the organizational and legal framework of functionality of youth parliamentary structures. The authors develop a model of systemic assessment of the effectiveness of youth parliamentary structures based on the five key vectors of activity of these institutions: legislative, project, personnel training, and the organization of socially significant events. The need is substantiated for implementing such methodology of assessment and comparison of the effectiveness of activity of youth parliamentary structures in different regions of the Russian Federation for the purpose of determining most successful strategies of fulfillment of their functionality. The novelty of this work consists in the detailed analytical overview of the doctrinal and legal definitions of the youth parliament, as well as in elaboration of practical approach towards assessing the activity of regional youth parliamentary structures. The main result of the conducted research lie in the original (proposed by D. A. Fedotov) procedure for calculating the key performance indicators and efficiency coefficient. It is proven that introduction of universal indicator of youth parliamentary structures would eventually stimulate the development of youth parliamentarism in the Russian Federation. The authors formulate the assessment criteria for each vector of activity of the youth parliamentary structures. The future implementation of the all-Russian rating model would increase the effectiveness and coordination of interaction between the youth parliaments and civil society institutions