Tehran University of Medical Sciences Iranian Journal of Psychiatry 1735-4587 21 2 2026 02 21 179 191 EN Fatemeh Serjouie Department of Clinical Psychology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Amir Sam Kianimoghadam Department of Clinical Psychology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Hoda Doosalivand Department of Clinical Psychology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Zeinab Farjampanah Department of Clinical Psychology, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran. Abbas Masjedi-Arani Department of Clinical Psychology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran. 2025 06 12 2025 11 26 Objective: Childhood trauma and attachment styles are critical factors influencing prolonged grief symptoms in bereaved adults. This study investigates the relationship between childhood trauma, attachment styles, and prolonged grief symptoms considering the mediating role of mentalization, shame, and guilt in bereaved adults. Method: The present research is a cross-sectional descriptive study with a correlational design utilizing path analysis. The statistical population of this study includes bereaved individuals, selected by the convenience sampling method. A total of 311 participants completed to the PG-13-R, CTQ, RAAS, RFQ, and SSGS questionnaires. SPSS 24 and PLS 3 were employed for data analysis using path analysis modeling. PLS-SEM, a variance-based approach suitable for non-normal and complex models with multiple mediators, was used for path analysis modeling. Results: The study results demonstrated a significant direct relationship of childhood trauma (β = 0.29, P = 0.006) and attachment styles (β = 0.23, P = 0.020) with prolonged grief symptoms. The critical finding in this research concerns the mediating variables. According to the results, shame significantly mediated the overall model (β = 0.10, P = 0.042), specifically between between attachment styles and prolonged grief symptoms (β = 0.10, P = 0.044), while mentalization and guilt were not significant mediators. In total, 60% of the variance in prolonged grief symptoms can be explained by predictive variables (R² = 0.609), including childhood trauma, attachment style, mentalization, shame, and guilt. Conclusion: These findings emphasize the role of shame in the prolonged grief symptoms among adults with childhood trauma histories and insecure attachments. Therefore, the findings suggest that interventions targeting shame could be effective in reducing prolonged grief symptoms. https://ijps.tums.ac.ir/index.php/ijps/article/view/4153 https://ijps.tums.ac.ir/index.php/ijps/article/download/4153/1325