Suicidal ideation and suicide attempts are debilitating mental health problems and often treated with "indirect" psychotherapy, i.e. psychotherapy focussing on other mental health problems such as depression or personality disorders. We aim to study the effects of direct and indirect psychotherapy on suicidal ideation and incidence of suicide attempts. For this meta-analysis (CRD42020140573) we systematically searched PubMed, Embase, PsycINFO, Web of Science, Scopus and The Cochrane Central Register of Controlled Trials for papers published up to 1 April 2023 (updated each year). We included randomised controlled trials on psychotherapy targeting any mental health problem, delivered in any setting, compared with any control group, and reporting suicidal ideation or suicide attempts (including self-harm leading to hospitalisation). Studies measuring suicidal ideation with 1 item were excluded. Summary data were extracted and pooled (Hedges' g for suicidal ideation and relative risk for attempts), using three-level meta-analyses. After identifying 15006 studies, we included 147 studies comprising 193 comparisons and 11.001 participants. Direct and indirect psychotherapy conditions effectively reduced suicidal ideation (direct: g = -0.39 [-0.53; -0.24], I2 = 83.2; indirect: g = -0.30 [-0.42; -0.18], I2 = 52.2). Direct and indirect psychotherapy conditions also effectively reduced suicide attempts (direct: RR = 0.72 [0.62; 0.84], I2 = 40.5; indirect: RR = 0.68 [0.48; 0.95], I2 = 0). Sensitivity analyses largely confirmed these findings. Direct and indirect interventions reduce suicidal ideation and suicide attempts with similar effects. Suicide prevention strategies could make more use of indirect treatments to get effective interventions to people who usually do not get treatment for suicidal ideation or self-harm.