Schizophrenia poses significant societal challenges, including interpersonal tension, an increased risk of suicide, and soaring medical costs. Although antipsychotics can prevent relapses, they often give rise to adverse effects and do not provide lasting relief. Mindfulness-based interventions (MBI) emerge as a hopeful avenue for improving outcomes. However, existing research and meta-analyses of the efficacy of MBI in schizophrenia remain limited. This study aimed to evaluate the efficacy of MBI as an adjunctive therapy for schizophrenia. Relevant randomized controlled trials (RCTs) were searched across PubMed, Embase, Web of Science, and Cochrane Library from inception dates up to January 12, 2023. Statistical analyses were conducted using Stata software (version 15.0) and Review Manager 5.4. The quality of the included RCTs was assessed using the revised Cochrane risk of bias tool. A total of 18 RCTs were included, with 675 patients and 704 health controls. Our meta-analysis revealed that MBI significantly improved psychosocial function, insight, and mindfulness in individuals with schizophrenia. The quality of the included RCTs had a low to moderate risk of bias. These findings suggest that MBI holds promise for improving the mental health of individuals with schizophrenia.