【Abstract】 Objective To investigate the cl inical effect of transplanting by auto-fat granule injection for mastatrophy post suckl ing. Methods From March 2000 to June 2006, 73 patients(146 breasts ) with mastatrophy post suckl ing were treated by transplanting auto-fat granule. The mastatrophy occurred between ages 28 and 52 years with a median of 37 years post suckl ing. The breasts shrank and their elasticity decreased gradually within 2-10 years post suckl ing. The autofat granule was obtained by l iposuction with syringe from patient’s abdomen, waist, buttocks and thighs, etc. After repeated wash and purification, the auto-fat granule was transplanted into the interspace behind the breast by injection. The quantity of auto-fat granule was 50-100 mL in each side of breast per transplantation at 3-6 months intervals, and the whole course of treatment needed 2-6 transplantations. Results The incisions in all cases healed primarily postoperatively. In 73 cases, 65 were followed up from 6 months to 3 years post operation. All patients had a significant improvement in their breast size and shape postoperatively and their breasts were soft and natural in appearance and feel. All of them had more perfect arcuation ofphysique and body with strengthened self-confidence, rel ieved mood and improved qual ity of l ife. However, small indurations were found sporadically in 7 cases (10 breasts) within 2-7 months, and calcifications in 5 cases (8 breasts) within 9-14 months post the first operation. Conclusion The transplantation by auto-fat granule injection for mastatrophy post suckl ing is an effective and practical method. The surgical technique is well worth performing in cl inical practice.