Researches focused on the issues of alcohol addiction performed in the Czech Republic show that the number of alcohol addicts is higher every year and alcoholism has become a serious public health problem. There are more and more addicts every year, which is except others backed by the words that MUDr. Petr Popov, senior consultant of the Addiction Treatment Department of the General Faculty Hospital in Prague, said to the Právo daily on 10 March 2010: ?We used to have about 300 thousand alcohol addicts. Now there are between 600 and 700 thousand. There are twice as many men as women, but women have been gaining on men?. As an article in the Mladá Fronta Dnes of 21 February 2012 says, the number of young alcohol consumers is increasing, while about a fifth of 16 year olds admit drinking five or more glasses at least three times a month. This results from 2011 research quoted in the above article. My thesis dealing with the issues of alcohol addiction in teenagers wants to map the situation among teenagers of České Budějovice region and their knowledge of the impacts of excessive alcohol consumption on their personal and family lives, social lives and relations. The theoretical part deals with the problems of the process and occurrence of alcohol addiction in general and with the social and health consequences of excessive alcohol consumption, with the factors influencing teenagers to consumption of alcohol and other drugs and prevention in the field of addiction focused on teenagers. In the research part I particularly focus on socioeconomic background of young respondents, personal experience with alcohol and marginally on the other addictive substances. I also focus on mapping the knowledge of the consequences of alcohol consumption, influence of environment and of free time activities. I applied quantitative research, in the form of a questionnaire. My research shows that most of teenagers are aware of the consequences of alcohol consumption or abuse, but they do not limit alcohol consumption in their lives and they actually increase its consumption as they are growing older. More systematic application of training seminars focused on more consistent care about personal and social development and better orientation of free time activities can definitely contribute to prevention of alcohol abuse, of addiction development among teenagers, to further improvement of their knowledge and skills used for alcohol consumption reduction and consequent addiction. Better legislation measures in the field of punishing young users of alcohol and drugs would undoubtedly contribute as well.