Underage drinking is a public health concern. However, few studies have examined the association between alcoholic beverage advertising and underage drinking, particularly in countries with low underage drinking rates, such as Japan. Therefore, we aimed to investigate the relationship between exposure to advertising in various media and alcohol drinking among Japanese adolescents. We conducted a cross-sectional study involving 15,683 adolescents (51% girls) using data from a nationwide lifestyle survey in 2021 among junior and senior high schools across Japan. Media types were websites, stores, and public transportation. We defined current drinking as alcohol consumption of ≥1 day in the 30 days preceding the survey. Multivariable logistic regression was used to examine the association between exposure to alcohol advertisements and current drinking, adjusting for sex, grades, school area, lifestyle (bedtime and having fun at school), and addictive behaviors (smoking status and parents' alcohol consumption). The prevalence of current drinking was 2.2% (2.3% of boys and 2.0% of girls). Students who were exposed to any alcohol advertising media had higher odds of current drinking compared with those who were not (odds ratio, 1.48; 95% confidence interval [CI], 1.18-1.87). Students who were exposed to web, in-store, and public transportation advertisements had odds ratios of 1.44 (95% CI, 1.14-1.81), 1.62 (1.28-2.05), and 1.45 (1.06-1.98) of current drinking, respectively, compared with those who were not. The association of exposure to alcohol advertising media with the prevalence of current drinking was similar among boys and girls (all p for sex interaction >0.1), except for that of exposure to web advertisements; its association with current drinking was more pronounced in girls (p for sex interaction = 0.046). Exposure to a larger cumulative number of different alcohol advertising media was independently associated with a higher prevalence of current drinking among all students, boys, and girls (p-values for trend <0.001, 0.031, and <0.001, respectively; p for sex interaction = 0.085). We found an association with a dose-response relationship between exposure to alcohol advertisements and current drinking among adolescents in junior and senior high schools across Japan. Our findings highlight the need for further advertising regulations to prevent underage drinking.