The present study examines several types of social anxiety that may be associated with the onset of alcohol use in middle school students, and whether the relationship differs by sex and grade. Students in the seventh and eighth grades (N = 2,621) completed the Social Anxiety Scale for Adolescents and a measure of lifetime drinking via schoolwide surveys. Distinct aspects of social anxiety were associated with higher and lower rates of onset of alcohol use. A high level of fear of negative evaluation was associated with drinking initiation in boys and girls, while girls who reported no social anxiety or distress in new situations were more likely than other groups to have started drinking by early adolescence. Youths with either very low or very high levels of generalized anxiety had higher rates of drinking than youths with scores in between. These findings suggest that the relationship between social anxiety and initiation of alcohol use is complex and varies by type of anxiety symptomatology. (Contains 2 tables and 2 figures.)