Abstract Background Breast cancer is a common form of cancer in women, with 28% newly diagnosed in the UK in 2020. Botulinum toxin A (BONT-A), first used for strabismus treatment, could be used in breast surgery to address postoperative complications. This study aims to investigate the efficacy of the implementation of BONT-A on various breast surgeries. Method A systematic literature review was conducted with 57 studies identified, including 6 RCTs, 1 retrospective chart review, and 1 case report. Data extraction and analysis were done using PRISMA, ROBVIS, and GRADE, including improvements in post-operative pain and upper limb impairments, capsular contracture, and scar minimization. Results The studies involved 347 patients and examined the role of BONT-A in breast reconstruction. Studies reported no clinically significant change in pain intensity up to 6 months from a single administration of BoNT-A (mean 13/100; 95% CI, -4 to 31). Studies showed that after 9 months of 100U intradermal injection, there is improved scar development (15.17±7.6 vs. 13.04±5.44, p=0.034 on the POSAS scale), were smoother (37.46±7.51 vs. 56.77±32.03, p=0.003 at 9 months), with reduced width (p<0.001), reduced early post-operative formation (9 vs. 6 P=0.001 on VSS), and improved capsular contractures. There have been no major adverse events reported across all studies. Conclusion BoNT-A may reduce scar formation but lacks evidence for managing postoperative complications, requiring further RCT and observational studies.