One of the most common adverse outcomes of an upper blepharoplasty involving double-eyelid surgery is asymmetric upper eyelids due to unbalanced supratarsal folds or a difference in the palpebral fissure height. This study aimed to evaluate the efficacy and safety of transconjunctival levator aponeurosis-Müller muscle complex plication for correcting acquired ptosis following double-eyelid surgery. This retrospective study evaluated 18 patients who underwent transconjunctival levator aponeurosis-Müller muscle complex plication between June 2016 and June 2019 to correct acquired ptosis. On the basis of the main area of eyelid drooping, ptosis was categorized as central (mid-pupillary), medial (medial limbus), or lateral (lateral limbus). Preoperative and postoperative palpebral fissure heights were measured and compared. Three months postsurgery, the mean difference in palpebral fissure height between bilateral eyes decreased from 0.96 to 0.04mm in the medial ( P <0.001), from 0.93 to 0.00mm in central ( P =0.003), and from 1.30 to -0.03mm in lateral ptosis ( P =0.079). In 13 patients who underwent unilateral correction, the amount of plication was significantly associated with increased palpebral fissure height at the medial limbus ( P =0.043) and mid-pupillary line ( P =0.035). All patients reported a significant improvement in satisfaction. Five patients experienced acute postoperative complications, including chemosis, conjunctival injection, and foreign body sensation, all of which were resolved after a month of observation. No asymmetries or recurrences were observed. Transconjunctival levator aponeurosis-Müller muscle complex plication is a minimally invasive, safe, and effective technique for correcting acquired ptosis following upper eyelid surgery.