The article tackles the problem of teenagers’ addiction to online games. In the process of digitalization of modern society, the world of games has changed significantly as one of the teenagers’ principal activities. And therefore, online games have become an important part of teenager's everyday life. The article characterizes the features of such games (accessibility, continuity, versatility, incompleteness, creative nature). Internal and external factors of addiction to online games as well as gamers’ socio-psychological features that contribute to the formation of addiction are analyzed. The article focuses attention on the positive and negative impact of online games, which, on the one hand, is considered as the means of socializing teenagers, and on the other hand, may lead to addiction development. The analysis of scientific literature makes it possible to consider “online gaming addiction” as a type of non-chemical addiction; narrow, single-minded use of the Internet, an obsessive need to play online, the characteristics of which are concentration of attention, intensity of emotions, escape from reality and life problems solving. It is emphasized that the consolidation of addiction takes place by transferring the gamer’s attention from the game plot to communication with other participants – finding like-minded people. The purpose of the article is to analyze the signs, causes and consequences of teenagers’ addiction to online games and to determine the features of social prevention of such addiction in teenagers. Methods of research: analysis and synthesis of theoretical sources, systematization, generalization and comparison in order to study the features of online games and their influence on teenagers, the causes and consequences of addiction from them; survey (questionnaire, independent interview), a modified method of identifying the level of self-esteem of an individual in interpersonal relationships, behavior, activities and feelings (S.Budassi). While conducting the research, the reasons for the persistent interest of teenagers in online games were singled out, among which the most important are: establishing communication in a peer groups, self-affirmation and self-realization, financial reward. The directions of social and preventive work with teenagers regarding the prevention of addiction to online games and its minimization are outlined, and the necessity for a systematic and comprehensive approach in this work is proven.