AbstractIntroductionThe internet has become a common space for adolescents to connect with others and find information. However, it remains unclear whether online encounters can serve as new sources of social support for Chinese adolescents. The present study aimed to identify distinct patterns in Chinese adolescents’ social support from both offline and online sources and to examine how these patterns relate to individual and family factors and adolescents’ mental health conditions.MethodsData were obtained from a cross‐sectional survey of 1031 Chinese adolescents (47.1% female, mean age = 13.67) in Foshan, Guangdong province. Latent profile analysis was performed with Mplus. Associations between the identified classes and auxiliary variables were examined with the “R3STEP” procedure and the DCON command in Mplus.ResultsWe identified four groups. Three groups showed consistent patterns in terms of receiving social support from offline and online sources, namely, the high support group (24.8%), moderate support group (43.8%), and low support group (15.3%), respectively. The fourth group received a moderate level of offline but low level of online support (16%), named the moderate offline‐low online support group. The groups differed in individual and family characteristics. Higher support was associated with higher life satisfaction, lower depression, and social anxiety, but also higher problematic internet use. Overall, the moderate offline‐low online support group showed better mental health than the other groups.ConclusionsOur study extends social support research by revealing heterogeneity in adolescents’ social support patterns. The findings encourage a balanced use of offline and online support.