This study aimed to examine the role of social support on international student's acculturative stress in Sebelas Maret University (UNS). A total of 111 students were chosen as population of this quantitative study. Considered by the limited population, previously, the study would be done by the population sampling. Fourthy eight samples were gathered by using incidental sampling and snowball sampling. Acculturative stress scale (Reliability 0,913) and social support scale (reliability 0,855) were used in this study. The result of regression analysis showed that social support significantly has a role on acculturative stress showed by Fcalculated > Ftable (8,451>4,05), p value 0,006 (p<0,05) and correlation coefficient (R) -0,394. Contribution of the predictor variable to the criterium variabel was -15,5%. Based on the study results it can be concluded that, social support has 15,5% negative role on the level of acculturative stress on international student that are learning in UNS.