The health and life expectancy of Finnish people are improving, however the health inequalities are a nation-wide problem. One of the public health goals in Finland has been to reduce alcohol use. Alcohol use among adolescents has been decreasing, but still the differences are explicit between the students at upper secondary school and vocational school. This Master’s thesis examined, are there differences in the decreasing trend of alcohol use among adolescents according to socioeconomic status and do loneliness, life satisfaction, family support or peer support explain possible differences. Alcohol use measures were drinking frequency and drunkenness during lifetime. Socioeconomic status was measured by parental occupation and perceived family wealth. The research data was from the Finnish part of the Health Behaviour in School-aged Children -study from the years 2002, 2006, 2010 and 2014. The target group was Finnish 15-year old adolescents. The research data consisted of 7432 adolescents, from which 3855 were girls and 3577 were boys. The used analysis methods were cross-tabulation, Pearson’s Chi-square test and binary logistic regression model. Adolescents’ alcohol use has decreased in all socioeconomic status groups during the study years. Alcohol use was more common among adolescents, who perceive their family wealth low. The association between perceived family wealth and alcohol use was stronger than with parental occupation and alcohol use. Drunkenness was more common among girls who perceived their family less well-off. These girls felt themselves lonelier, less satisfied with their lives and their family support to be lower compared to the rest of the girls. Health promotion programmes should focus on the vulnerable group of adolescents who perceived their family not well-off. It is essential to recognize the girls, who also feel lonely, dissatisfied with their lives and have weak family support during the delicate stage of their lives.