Malignant pleural effusion (MPE) is a frequently observed complication in advanced malignant tumors. Clinical studies have shown that lentinan for injection (LNT) is beneficial for improving patients' quality of life and prolonging their survival. The purpose of this meta-analysis is to evaluate the efficacy and safety of LNT combining cisplatin in the treatment of MPE. Randomized controlled trials (RCTs) of LNT combining cisplatin in the treatment of MPE were searched in 6 literature databases from the establishment time of each database by 2 researchers. According to the inclusion criteria, 2 researchers independently screened studies, assessed the risk of bias and conducted subgroup analyses for different outcome indicators according to the specific characteristics of the included literature. Analyzing the data by Revman software, and evaluating the stability of the results by Stata software. A total of 52 RCTs were included. The results showed that combined use of LNT and cisplatin could improve the treatment effect, and the difference between groups was statistically significant (RR = 1.40, 95%CI: 1.33 ~ 1.46, P < .001). And the combined use of LNT could increase the quality of life (RR = 1.45, 95%CI: 1.35 ~ 1.56, P < .001). The using of LNT could significantly decrease the incidence of gastrointestinal reactions (RR = 0.86, 95%CI: 0.78 ~ 0.94, P < .001). Sensitivity analysis results showed that there were no qualitative changes in the indicator, and suggested the possibility of publication bias. Available evidence suggested the combined use of LNT and cisplatin showed better efficacy in treating MPE without increasing ADR incidence than using cisplatin alone. LNT is an ideal treatment for MPE, which has high clinical application value.