Objective: To study the effect of a modified alar base cinch suture (ABCS) based on nasal musculature anatomy on the three-dimensional morphology of nasolabial region in patients after Le Fort Ⅰ osteotomy. Methods: In the study, 30 patients[11 males and 19 females, with an average age of (23.23±2.98) years]with skeletal Class Ⅲ malocclusion underwent orthognathic surgery between August, 2019 and January, 2020 to have the maxilla advanced no more than 4 mm in the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology were involved and were divided into the test and control groups based on the random number table.In the test group, the nasal musculature was identified and labeled before dissection and the ABCS was according to the label, while in the control group, the nasal musculature was directly sutured and knotted in the midline of nose without prepend labeling.All the patients underwent three-dimensional facial photos preoperatively and 6 months postoperatively by using 3dMD face system.On the three dimensional image, soft tissue landmarks of nasolabial region was identified by the same examiner.Fourteen measurements including straight distance, curve distance, angle and ratio were measured.Statistical analysis was done by using SPSS 22.0. Results: There were significant differences between the two groups in cutaneous height of upper lip (P=0.023) and in nasal tip protrusion-alar width (P=0.012).The increase rate of cutaneous height of upper lip and the decrease rate of nasal tip protrusion-alar width in the control group were significantly higher than that in the test group.The alar width and alar base width of the both groups were significantly increased compared with the preoperative level (P < 0.05).The nasolabial angle in the control group was significantly higher compared with the normal value, while there was no significant difference between the test group and the normal value. Conclusion: Compared with the conventional suture method, this modified alar base cinch suture is more favorable for the postoperative nasal coordination and nasolabial morphology in patients who need mild to moderate maxillary advancement, and it has certain advantages in operability and objective accuracy.So it could become a modified and accurate method of alar base cinch suture and be widely applied in clinical practice.