<p>Mental health problems are prevalent among Chinese college students, with over 20% experiencing disorders like depression. For primary education preservice teachers, these problems can affect their future teaching and student outcomes. This study examines the influence of childhood trauma on the mental health of primary education preservice teachers, focusing on rumination as a mediator and self-acceptance as a moderator. The research aims to uncover mechanisms contributing to mental health challenges among future educators. This study sampled 676 preservice primary school teachers from three universities in Shandong Province, China, and conducted a six-month follow-up survey. Childhood trauma significantly predicted rumination and mental health problems. Rumination mediated the trauma-mental health link, indicating that those who ruminate are more prone to mental health problems. Self-acceptance moderated these effects, with higher self-acceptance reducing the negative impact of trauma and rumination. The results validate the positive role of the Risk and Protective Factor Framework in understanding mental health problems. Addressing childhood trauma and rumination in mental health interventions for preservice teachers is crucial. Enhancing self-acceptance may protect against the adverse effects of trauma, promoting better mental health outcomes for future educators.</p>