An increased prevalence of common mental disorders and suicide has been reported among physicians worldwide. We aimed to assess which, if any, interventions are effective at reducing or preventing symptoms of common mental health disorders or suicidality in physicians.For this systematic review and meta-analysis MEDLINE, EMBASE, PsycINFO, and Cochrane CENTRAL (database inception to March 26, 2018), reference lists of included studies, and additional sources were systematically searched and screened by two independent reviewers. We included randomised controlled studies or controlled before-after studies of interventions to reduce depression, anxiety, or suicidality in physicians, as assessed by a validated outcome measure. Both organisation-level and physician-directed interventions were considered. Our primary outcome was differences in symptoms of common mental health disorders following intervention. We used random-effects modelling for the main meta-analyses and planned subgroup and sensitivity analyses. The study protocol is registered with PROSPERO, number CRD42018091646.We identified 2992 articles for screening, of which eight were included in the systematic review (n=1023 physicians) and seven in the meta-analysis. Results indicated a moderate effect in favour of the physician-directed interventions for reduction in symptoms of common mental health disorders (standardised mean difference 0·62; 95% CI 0·40-0·83; p<0·0001). Separate analyses showed physician-directed interventions resulted in reductions of symptoms of depression, anxiety, and suicidality. No evidence of significant heterogeneity was found (Q=3·78; p=0·44).Physician-directed interventions are associated with small reductions in symptoms of common mental health disorders among physicians. Research regarding organisational interventions aimed at improving physicians' mental health via modification of the work environment is urgently needed.Health Workforce Programme, Commonwealth Department of Health, Australian Government, iCare Foundation, and NSW Health.