The article presents the results of testing the measurement of social network group formation (hereinafter “SNGF”) within the framework of national projects as a new way to establish in the online network space the processes of formation and interaction of collective subjects (stakeholders) interested in the quality of development and specific results of project solutions. The identification and interpretation of the essential characteristics of collective subjects that have common or different interests, behavioral strategies, and goals can be measured sociologically in the process of group formation, which can result in fixing the origin of the activity of a new collective subjectness or new social groups. The General humanistic approach to society in modern sociology recognizes the importance of all social groups, since the difference in their position leads to different interests, the coordination of which is the main goal of state policy. During the development and implementation of project solutions, there are solution groups that are responsible for setting the problem, setting goals, and choosing the means to achieve them. The nature and contours of the solution groups within the framework of national projects are defined by the authorities, which set the criteria for processes of participation or exclusion of stakeholders in addressing important social issues and the ability to operationalize the design decisions. The testing of the SNGF is based on the materials of an online search study (2019) conducted in 4 constituent entities of the Russian Federation. The study was updated in the context of an academic project implemented by the Center for Sociology of Management and Social Technologies of the Federal Research Center of the Russian Academy of Sciences with the support of the Russian Scientific Foundation (Research Project No. 19-18-00345). Attention of the study is focused on the empirical measurement of the general trends of SNGFs through specially developed indices of network social subjectness, expressed in the online network interaction of regional stakeholders regarding the creation and resolution of problems, the search for constructive solutions to them or translation of the protests during the implementation of national projects. Three criteria for the diagnosis of social network subjectness are proposed: the availability, content and dissemination of targeted information from the authorities sufficient to activate and constructively include the population in management decisions; the presence/absence of online and offline forms of inclusion of the population (using its potential: information, knowledge, resources) in the implementation of national projects based on the organization of social feedback; the nature of interaction (neutral, oppositional, organizational and constructive) between authorities and the population in the network space during the implementation of national projects. It was revealed that each region has its own character and trends in the organization of the SNGF and own criteria of social subjectness. There is a low level of public satisfaction with the implementation of national projects due to certain barriers and difficulties, including poorly organized social-oriented feedback regarding the implementation of project decisions. That is, today the SNGF as a process of intensifying the online communication interaction of stakeholders to develop socially oriented solutions within the framework of national projects is poorly regulated by the authorities. The population is practically not seen as one of the main performers of project activities. The revealed information on the implementation of projects, disseminated to a greater extent by the authorities, is often declarative and projective. Test of the methodology for sociological measurement of SNGF will continue in 2021 during the network monitoring of the implementation of national projects.