Objective:To explore the clinical application of lateral thoracic artery perforator flap in repairing local defect after breast conserving surgery.Methods:The clinical data of 48 breast cancer patients planned to finish breast conserving surgery were retrospectively analyzed. The patients were divided into plastic breast-conserving group and routine breast conserving group. In the plastic breast-conserving group, 24 patients local defect repaired with the lateral thoracic artery perforator flap. In the routine breast conserving group, 24 patients local defect repaired with the fascial flap around the cutting edge. The operation related indexes and cosmetic effect from two groups were compared.Results:Both groups of patients successfully completed breast conserving surgery. The plastic breast-conserving group patients had significantly increased in operation time, operative blood loss, incision length and drainage tube indwelling time compared with the routine breast conserving group; the differences were statistically significant ( t=6.99, 9.37, 21.74, 8.80, P<0.05). The rate of secondary surgery enlarged was lower than fhat in the routine breast conserving group, and the difference was statistically significant (χ 2=4.76, P<0.05). There were 3 cases in the plastic breast conserving group and 1 case in the conventional breast conserving group. The skin at the edge of the flap was ischemic necrosis in the 4 cases, which healed after dressing change and drainage, and there was no significant difference ( P>0.05). The evaluation of postoperative cosmetic effect showed that the excellent and good rate of the observation group was 91.7%, compared with the routine breast conserving group (58.3%); the difference was statistically significant (χ 2=7.11, P<0.05). All patients were followed up for average 24 months, and local recurrence and distant metastasis were not observed. Conclusions:The lateral thoracic artery perforator flap for filling local defects in the lateral quadrant or central region of breast cancer is feasible, easy to operate, hides incision scar, better cosmetic effect and worthy of clinical promotion.