Objective To compare the effectiveness of different β-blockers for preventing postoperative atrial fibrillation (POAF) after cardiac surgery. Methods Databases of PubMed, Science Direct, Web of Science, The Cochrane Library, SinoMed, CKNI, VIP, WanFang were searched by the computer from inception to April 31, 2022 to collect randomized controlled studies on the comparison of the effectiveness of different β-blockers for preventing POAF. Two investigators independently screened the literature and extracted information. The quality of the literature was evaluated using Cochrane bias risk tool, and RevMan 5.3 and STATA 17.0 were used for meta-analysis. Results A total of 17 randomized controlled studies with 3 290 patients were included. Direct meta-analysis showed that landiolol and metoprolol were more effective than placebo (P≤0.001), and carvedilol was more effective than metoprolol in preventing the development of POAF (P<0.001). Network meta-analysis showed that landiolol, carvedilol and metoprolol were more effective than placebo in preventing the incidence of POAF (P<0.05). Landiolol and carvedilol were more effective than metoprolol, and carvedilol were more effective than nebivolol (P<0.05). The surface under the cumulative ranking curve from high to low were carvedilol, landilol, propranolol, atenolol, metoprolol, and nebivolol. Conclusion Carvedilol and landilol have different degrees of improvement in the occurrence of POAF, and carvedilol has the best preventive effect. More studies are required to verify the strength of evidence due to the limited sample size.