Objectives: The purpose of this study was to verify correlation between social support & psychosocial stress and drinking behavior after consuming alcohol among college students. Methods: This study surveyed by questionnaire 440 students who consumed alcohol regularly from 36 colleges around the country in 2014. Data were analyzed using the program SPSS 21. Results: The effects of social support on problem behavior after drinking and psychosocial stress had significant influence with each path coefficient -.178(CR= -3.408, p<0.001) and -.294(CR= -6.195, p<0.001). Also, the effects of psychosocial stress on problem behavior after drinking had significant influence with path coefficient -.141(CR= -2.858, p<0.05). Social support had significant influence(p<0.001) on problem behavior after drinking through psychosocial stress, serving as a mediator variable, and social support had significant influence on problem behavior after drinking through psychosocial stress. Conclusions: Problem behavior after consuming alcohol held strong relevance in social support and psychosocial stress.