A line under the eye that looks like a silkworm is mostly caused by localized skin folds. The skin under the eyes is loose and the subcutaneous tissue is not tightly adhered, so it is easy to form skin folds, especially in older people, who experience skin laxity due to aging. Skin folds in the eye are not a disease and can be left untreated as they do not affect normal eye health or eye function. However, if the patient feels that the skin folds are affecting his or her appearance, they can be treated with cosmetic ophthalmic plastic surgery. Surgical treatment can usually be performed to remove the excess loose skin and tighten the localized skin so that the skin folds will disappear and improve the appearance. The design of the specific surgical procedure must be done after an in-person examination, and the surgeon will develop an individualized plan based on the characteristics of the patient’s facial shape. It is recommended that patients with abnormal eye appearance and other discomforts should seek medical attention to evaluate their condition and follow the doctor’s instructions for treatment.