This study aimed to assess Problematic Social Media Use (PSMU) among Iranian adolescents and explore potential risk and protective factors. In the present cross-sectional study, 3375 Iranian adolescents were recruited online and completed questionnaires. Latent profile analysis (LPA) was performed to identify groups with various levels of PSMU. Indicator variables included standardized factor scores for PSMU, attention-deficit/hyperactivity disorder, sensation-seeking, internet addiction, loneliness, social anxiety, internalizing symptoms, social support and self-esteem. Five groups were identified relating to severities of PSMU and other factors: low-risk: n = 823 (24.4 %); low-to-moderate-risk: n = 835 (24.7 %); moderate-risk: n = 630 (18.7 %); moderate-to-high-risk: n = 584 (17.3 %); high-risk: n = 503 (14.9 %). Multiple factors, including sensation-seeking, internalizing symptoms, social anxiety, loneliness, internet addiction, attention-deficit/hyperactivity disorder, low self-esteem and low perceived social support, statistically predicted PSMU. The current findings may help identify Iranian adolescents who are particularly vulnerable to PSMU and assist in intervention development.