Previous research has suggested that Asian Americans (AAs) are less likely to mobilize social support, and find support to be less helpful, when compared with European Americans (EAs). In a 10-day daily diary study of AA and EA college students, we hypothesized that AAs would activate support less frequently than EAs for both stressful and positive events, a cultural difference that would be mediated by group harmony values. We also predicted that AAs would find support to be less helpful, and we explored differences in the sources of support used. Results confirmed that cultural differences in support use were partially mediated by the value of maintaining group harmony through emotional restraint. AAs also perceived received support to be less helpful and more frequently used discretionary rather than kinship support sources. Findings suggest that naturalistic support experiences differ markedly for these groups, with implications for help-seeking behavior and mental health services.