Objective To systematically evaluate qualitative studies on the experience of peer support for breast cancer patients, and to provide references for the application of peer support in breast cancer patients. Methods We searched databases including the Cochrane Library, Embase, PubMed, CINAHL, Web of Science, PsycINFO, CNKI, WanFang, VIP and CBM to collect qualitative research on the experience of peer support for breast cancer patients. The retrieval period was from inception to May 2022. The quality of the included studies was evaluated based on Joanna Briggs Institute Critical Appraisal Tool for qualitative research. The results were integrated by the method of aggregative integration. Results A total of 12 studies were included, and 55 results were extracted and summarized into 10 categories, which were synthesized into 3 integrated results:motivations of breast cancer patients to participate in peer support, benefits of breast cancer patients participate in peer support, and challenges of breast cancer patients to participate in peer support. Conclusion Participation in peer support brings multiple benefits to breast cancer patients. In future research, it is necessary to improve the matching mechanism between the 2 sides of support, develop the standardized peer support protocols, and enrich the form of peer support, in order to promote the continuous improvement and development of peer support application in breast cancer patients in China.