Introduction: Traumatic life events (TLE) and difficulties in emotion regulation (ER) can be considered risk factors for the development of gambling disorder in adolescents and young adults. Methods: The aim of the present study was to examine the differences in TLE, ER strategies, positive and negative affect, and gambling severity in a clinical sample of individuals undergoing treatment for gambling disorder (92.8% males; Mage 5 24.83, SD 5 3.80) and a healthy control group (52.4% males; Mage 5 15.65, SD 5 2.22). The relationship between the variables was assessed and the mediating role of ER in the relationship between TLE and gambling in the clinical sample was analysed. Results: The results showed higher scores in gambling severity, positive and negative affect, ER strategies and TLE in the clinical sample. In addition, the severity of gambling was positively correlated with TLE, negative affect and with rumination. TLE were also correlated positively with negative and positive affect, rumination ER strategies, plan focus, positive reinterpretation, and catastrophizing. Finally, rumination mediated the relationship between TLE and gambling severity. Conclusions: These findings may have relevant implications for the prevention, understanding and treatment of gambling disorder.  Kulcsszavak: traumatic life events, emotion regulation, gambling disorder, adolescents, young adults