Purpose: This study was to explore the prevalence of alcohol experiences and to identify the expectancy on the effects of alcohol and alcohol knowledge in early adolescents. Method: The cross-sectional survey of 1854 students from seven middle schools in one district of Seoul was conducted by convenience sampling. Alcohol experience and early onset of alcohol use were measured by the Youth Risk Behavior Survey. Alcohol expectancy was measured by an Alcohol Effects Questionnaire. Result: Over sixty five percent of adolescents reported that they had previous drinking experiences. The participants with no alcohol drinking experience had a lower level of alcohol knowledge than those with experience(t=2.73, p=.007). In expectancy on effects of alcohol, girls had a more positive alcohol expectation than boys(t=-2.54, p=.011). Alcohol knowledge negatively correlated with alcohol expectancy(r=-.40 p=.000). In regression of alcohol expectancy, gender and alcohol knowledge were significant predictors explaining 17%. Conclusion: The results support that alcohol expectancy is an important link with early drinking experiences and alcohol knowledge, focusing on the importance of gender differences. Therefore, an alcohol prevention program in early adolescence is needed and should be focused on multidimensionality of the alcohol expectancy with developmental and psychosocial factors for early adolescents.