Objective: To evaluate the surgical treatment outcome of upper eyelid entropion after ptosis correction and analyze the complicated causes. Methods: A retrospective analysis was performed on patients who underwent surgical treatment for complicated upper eyelid entropion after ptosis correction and were followed up for more than 6 months at Zhongshan Ophthalmic Center from January 1, 2015 to June 30, 2020. Pre- and postoperative lid height, lagophthalmos, upper lid margin curvature, eyelid entropion and corneal fluorescein staining scores

were evaluated. Results: A total of 18 cases (19 eyes) were included, among which 17 cases (18 eyes: 8 eyes of ptosis overcorrection, 6 eyes of ptosis undercorrection, and 4 eyes with normal eyelid height) were post-frontalis flap suspension, and 2 cases (2 eyes: 1 eye of ptosis undercorrection, 1 eye of ptosis overcorrection) post-levator resection. All patients had a complete correction of upper eyelid entropion and a significant reduction in corneal epithelial fluorescein staining score (P<0.05). Both the complicated ptosis undercorrection and overcorrection were treated with satisfactory outcome. Correction of entropion did not change the eyelid height in patients with preoperative normal height. The intraoperative findings showed that several factors related to original ptosis surgery may be involved in complicated upper eyelid entropion, including: the skin incision too close to the upper lid margin, excessive resection of the orbicularis oculi muscle along the eyelid margin, poor separation of the frontalis muscle flap, inappropriate eyelid plate fixation site of the frontalis muscle flap, and ptosis overcorrection caused by inaccurate evaluation of the intraoperative eyelid height, etc. Conclusion: Surgical treatment of the upper eyelid entropion secondary to ptosis correction is safe and effective, but is complicated and difficult. Skillful ptosis surgery and appropriate surgical techniques are crucial to reduce its occurrence.