Ptosis, also known as upper eyelid ptosis, is a partial or complete loss of function of the muscles that lift the upper eyelid, resulting in partial or complete drooping of the upper eyelid. In mild cases, the pupil is partially covered, or in severe cases, the entire pupil is covered, which is not only aesthetically displeasing and affects vision, but can also cause severe amblyopia in children who were born with it. In order to overcome the visual impairment, patients often tighten the frontalis muscle to raise the upper lid margin, deepening the frontal wrinkles on the affected side and raising the eyebrows. If the upper lid is bilaterally ptosis, the head is tilted up to look at things, creating a special (“skyward”) posture. Ptosis in children is mostly congenital, and it not only affects the child’s vision development, but also contributes to low self-esteem. If the pupil is obscured, surgery should be performed as soon as possible to avoid amblyopia. In adults, ptosis is mostly congenital and is caused by neurological, other ocular or systemic diseases. Ptosis is a common condition in ophthalmology, and the surgical procedure is well established and effective, with physiological and cosmetic requirements.