Background: The serratus anterior plane (SAP) block is a newer method that can be used in patients undergoing thoracic surgeries. The postoperative analgesia efficacy of SAP blocks for thoracic surgery remains controversial. We conduct a meta-analysis to evaluate the analgesia of SAP blocks after thoracic surgery. Methods: We searched PubMed, Embase, EBSCO, the Cochrane Library, Web of Science, and CNKI for randomized controlled trials (RCTs) regarding the postoperative pain control of a SAP block on thoracic surgery. All of the dates were screened and evaluated by two researchers and meta-analysis was performed using RevMan5.3 software. Results: A total of 8 RCTs involving 542 patients were included. The meta-analysis showed statistically significant differences between the two groups with respect to postoperative pain scores at 2 h (standardized mean difference [Std.MD] = -1.26; 95% confidence interval [CI] = -1.66 to -0.86;P < .0001); 6 h (SMD = -0.50; 95%CI = -0.88 to -0.11;P = .01); 12 h (SMD = -0.63; 95%CI = -1.10 to -0.16;P = .009); 24 h (SMD = -0.99; 95%CI = -1.44 to -0.51;P < .0001); postoperative opioid consumption at 24 h (SMD = -0.83; 95%CI = -1.10 to -0.56;P < .00001); and postoperative nausea and vomiting (PONV) rates (RR = 0.39; 95% CI = 0.21-0.73;P = .003). Conclusion: The SAP block can play an important role in the management of pain after thoracic surgery by reducing both pain scores and 24-h postoperative opioids consumption. In addition, there is fewer incidence of PONV in the SAP block group.