Objectives: Mindfulness-based interventions (MBIs) can effectively relieve negative symptoms in patients with schizophrenia. However, the effect size of MBIs and their potential influencing factors remain unclear.Methods: We searched different databases and performed a meta-analysis to determine the efficacy of MBIs for the treatment of negative symptoms in schizophrenia. Standard mean differences (SMDs) with 95% confidence intervals (CIs) were calculated to assess effect sizes of MBIs for negative symptoms. Subgroup analysis and meta-regression analysis were used to explore the potential influencing factors of the pooled SMD of MBIs for negative symptoms.Results: We identified 26 randomized controlled trials including 1725 individuals with schizophrenia. We observed a small-to-large effect size of MBIs for negative symptoms. The pooled SMD of MBIs for negative symptoms was − 0.59 (95% CI: − 0.87 to − 0.32), with a heterogeneity (I2) of 83.6% (95% CI: 76.9 to 88.4%; p < 0.01) based on a random effects model. In the subgroup analysis, significant differences were found with “Different Geographical Location of Treatment Study” (p < 0.01) and “Different Lengths of MBIs treatment” (p = 0.02). Meta-regression analysis showed that publication year was a significant predictor of the effect size of MBIs for negative symptoms (p < 0.001).Conclusions: We identified a small-to-large effect size of MBIs to relieve negative symptoms in patients with schizophrenia. The number of sessions and different cultures were associated with the efficacy of MBT for negative symptoms.