{"__content__"=>"\n Abstract\n \n \n Registration\n \n ", "p"=>[{"__content__"=>"Adverse childhood experiences (ACEs) significantly influence the development of suicidal ideation (SI) in young people. Psychological factors are critical mediators in this relationship, yet the underlying psychological mechanisms remain unclear. This study aims to identify the psychological mediating/moderating factors between ACEs and SI among young people, thereby providing scientific evidence and theoretical support for formulating targeted psychological intervention strategies and reducing the risk of suicide. We searched six databases (PubMed, Embase, Web of Science, the Cochrane Library, CNKI, and Wan Fang) from their inception to June 23rd, 2025. Eligible studies were cross-sectional or cohort designs investigating psychological mediators/moderators between ACEs and SI in young people. The methodological quality of the included studies was assessed using the Joanna Briggs Institute critical appraisal checklists for cross-sectional studies and the Newcastle-Ottawa Scale for longitudinal studies. The results were synthesized using a narrative synthesis. This systematic review was reported in accordance with the PRISMA 2020 guideline. Among the 54 included studies, we identified 45 psychological mediating/moderating factors. These factors are classified as protecting and deteriorating factors. Among them, we found that negative emotions, negative thought patterns, and positive psychological traits were the mostfrequently examined factors. This study further summarizes the potential psychological pathways linking ACEs and SI in young people, thereby clarifying future intervention directions. It also suggests that future intervention programs should be diversified and targeted, so as to intervene early in young people’s SI and reduce their suicide risk. Future longitudinal cohort studies should verify the temporal and causal relationships suggested by this review."}, {"__content__"=>"The protocol has been registered in PROSPERO (ID CRD420251054107)."}]}