Background: Experimental studies have reported that angiotensin receptor blockers (ARBs) increase the risk of surgical complications. However, clinical data on their effect on surgical outcomes are limited.The aim of this study was to investigate the impact of perioperative use of ARBs on the outcomes of breast reconstruction using population-based claim data.Methods: Data of patients who underwent direct-to-implant or abdomen-based autologous breast reconstruction after total mastectomy from April 2015 to December 2018 were obtained from the Health Insurance Review and Assessment Service database. The patients were categorized as ARB, non-ARB, control, and non-hypertension groups. The effects of ARBs on surgical complications, length of hospital stay, and complication-related medical costs were evaluated.Results: Of the 9,036 patients who met the inclusion criteria, 5,192 underwent direct-to-implant reconstruction, and 3,844 underwent abdomen-based autologous reconstruction. The length of hospital stay was the longest and the surgical complication rate and complication-related medical cost were the highest in the ARB group after both reconstruction methods. Compared with non-treatment with antihypertensive drugs, ARB use was found to be an independent risk factor for surgical complications in direct-to-implant reconstruction [odds ratio (OR), 1.96; 95% confidence interval (CI), 1.09-3.50; P=0.0237] and complicationrelated medical cost (OR, 1.93; 95% CI, 1.10-3.40; P=0.0221) in abdomen-based autologous reconstruction.Conclusions: Perioperative ARB use was associated with adverse postoperative breast reconstruction outcomes. These findings might have a significant impact on perioperative antihypertensive management; nevertheless, further studies are warranted to confirm the study findings.