Background: The study aimed to assess the effects of breast-conserving surgery (BCS) versus mastectomy on survival and quality of life in stages I, II and III breast cancer, providing solid evidence for clinical decisions.Methods: We conducted a meta-analysis of randomised controlled trials on breast cancer treatments, searching databases such as PubMed and the Cochrane Library to compare BCS and mastectomy’s effects on survival and quality of life. A combined total of 16,734 patients in the control group and 17,435 patients in the experimental group were included in this analysis. This meta-analysis used RevMan 5.3 (Cochrane Collaboration, Copenhagen, Denmark) software for analysis.Results: Our meta-analysis of 34,169 patients from 11 studies showed that BCS significantly reduced the overall recurrence rate at a median follow-up of 29 months, with a mean difference of 1.27 and a 95% confidence interval (CI) of 1.19–1.36, strongly supporting its effectiveness (p<0.00001).Furthermore, our analysis found no significant increase in 5-year local recurrence rates for BCS versus mastectomy, indicating its long-term effectiveness with a mean difference of 1.13 (95% CI: [1.03, 1.24], p = 0.01). Additionally, there was a notable decrease in tissue ischemic necrosis among patients who had received BCS, with a mean difference of 0.37 (95% CI: [0.33, 0.42], p<0.00001), underscoring its benefits and long-term viability.Conclusion: Breast-conserving surgery resulted in fewer cases of tissue ischemic necrosis and higher body image scores compared with mastectomy, suggesting it is a preferable option for better cosmetic outcomes and potentially favourable effects on prognosis and quality of life.