Tehran University of Medical Sciences Iranian Journal of Psychiatry 1735-4587 17 3 2022 06 19 341 349 Samin Masoumi Department of Psychology, Faculty of Humanities, Zanjan University, Zanjan, Iran. Mohsen Amiri Department of Psychology, Faculty of Humanities, Zanjan University, Zanjan, Iran. Majid Yousefi Afrashteh Department of Psychology, Faculty of Humanities, Zanjan University, Zanjan, Iran. 2020 12 13 Objective: Perceived social support (PSS) and emotional self-regulation have customarily been related to greater psychological well-being, but the pathways via which perceived social support and emotional self-regulation increase psychological well-being have not been revealed. We investigated how much self-compassion mediated the association between perceived social support and emotional self-regulation in psychological well-being of breast cancer sufferers. Method: A cross-sectional study design was used. Participants were recruited from three oncology departments in Zanjan, Iran. Data was collected from breast cancer patients (n = 300). Participants completed self-report measures, the short Ryff scale Psychological Well-being (RSPWB), Emotion Regulation Questionnaire (ERQ), Multidimensional Scale of Perceived Social Support (MSPSS) and Self-Compassion Scale (SCS). Pearson correlation coefficient was used to assess association among the study variables and multivariable regression analysis was used to assess linear relationships among predictor variables (emotional self-regulation, perceived social support and self-compassion) and criterion variable (psychological well-being). Bootstrapping analyses were used to test the significance on indirect effects. Results: Bootstrapping analyses revealed significant indirect effects of perceived social support (β = 0.055, SE = 0.45, P = 0.049, 0.95 CI: LL = 0.0092, UL = 0.1345) and emotional self-regulation (β = 0.079, SE = 0.079, P = 0.004, 0.95 CI: LL = -0.0331, UL = -0.1358) on psychological well-being through self-compassion. Conclusion: These findings present new evidence that self-compassion may be a target for psychological interventions attempted at enhancing psychological well-being in cancer populations, particularly breast cancer survivors. https://ijps.tums.ac.ir/index.php/ijps/article/view/2495 https://ijps.tums.ac.ir/index.php/ijps/article/download/2495/1068