ObjectiveThis paper aims to evaluate the literature on the prevalence of psychological distress and its associated factors in patients with breast cancer.DesignSystematic review and meta-analysis.Data sourcesPubMed, Web of Science, Embase, the Cochrane Library, China National Knowledge Infrastructure and Wanfang were searched from inception to 11 June 2024.Eligibility criteriaStudies reported data on the prevalence and correlates of psychological distress were included. Review, letter, conference abstracts and articles not available in English and Chinese were excluded.Data extraction and synthesisTwo researchers independently conducted literature screening, data extraction and bias risk assessment. Meta-analysis was employed to estimate the prevalence and correlates of psychological distress in patients with breast cancer. The Agency for Healthcare Research and Quality and the Newcastle-Ottawa Scale were used for quality assessment. Meta-analysis was performed by using the R V.4.1.1 software.ResultsIn total, 34 studies representing 13 828 patients with breast cancer were included in the study. Most of the studies were cross-sectional study (n=25, 73.53%%). The pooled prevalence of psychological distress was 50% (95% CI 42% to 58%, I2=98%). Results showed that psychological distress was positively correlated with younger age (z=0.13, 95% CI 0.07 to 0.20), having children (z=0.39, 95% CI 0.11 to 0.61), poor financial situation (z=0.12, 95% CI −0.03 to 0.26), short time since diagnosis (z=0.19, 95% CI 0.01 to 0.36), previous treatment (z=0.15, 95% CI 0.03 to 0.27), distant metastasis (z=0.31, 95% CI 0.07 to 0.52), chemotherapy (z=0.22, 95% CI 0.05 to 0.38), prior emotional status (z=0.40, 95% CI 0.29 to 0.50), body image damaged (z=0.10, 95% CI −0.01 to 0.21), negative coping (z=0.12, 95% CI −0.11 to 0.34), communication avoidance (z=0.32, 95% CI 0.24 to 0.39) and negatively correlated with married (z=−0.25, 95% CI 0.45 to −0.02), high education level (z=−0.19, 95% CI −0.40 to 0.05), having insured (z=−0.04, 95% CI −0.15 to 0.08), full employment (z=−0.40, 95% CI −0.61 to −0.14), time of completion of treatment (z=−0.12, 95% CI −0.30 to −0.06), surgery (z=−0.05, 95% CI −0.53 to 0.45), social support (z=−0.18, 95% CI −0.29 to −0.06), post-traumatic growth (z=−0.19, 95% CI −0.34 to −0.03), good physical conditions (z=−0.17, 95% CI −0.29 to −0.04), positive coping (z=−0.22, 95% CI −0.53 to 0.15).ConclusionOur findings indicated that the prevalence of psychological distress in patients with breast cancers was 50% and 21 correlates of psychological distress. Screening and evidence-based interventions are urgent and essential to address this public concern and promote the health of patients with breast cancer.PROSPERO registration numberCRD42023397109.