Objective To explore the feasibility of using contralateral breast as the donor for immediately breast reconstruction or chest wall defect repair after mastectomy in breast cancer patients. Methods From Jul. 2013 to Mar. 2016, contralateral breast fat flap was used as the donor for 8 breast cancer patients with immediate autologous non-microsurgical breast reconstruction or chest wall defect repair after mastectomy. All participants in this study received preoperative oncological screening with ultrasound, mammography, and magnetic resonance imaging which revealed the absence of pathological abnormalities in the donor breast. Results Among the 8 pa-tients, 4 patients underwent immediate breast reconstruction and 4 received chest wall defect repair. Only 1 pa-tient undergoing breast reconstruction had minor complications with little or no effect on the final outcome. No patient undergoing chest wall defect repair had postoperative complications. The functional and aesthetic out-comes were very satisfactory. Regular follow-ups were from 3 to 34 months with no recurrence found up to the present. Conclusions This article presents the first case for immediately breast reconstruction or chest wall de-fect repair using contralateral breast as the donor. The surgical method has some complications but with good aesthetic outcomes, which can be an option for breast cancer patients with hypertrophic and ptotic breast.