Ectropion is an eversion of the eyelid due to various causes, and it mainly develops in the lower lid. Usually it shows a slow progression, and it is classified as involutional, cicatricial, paralytic and congenital. Acute idiopathic bilateral lower lid ectropion is very rare; few cases have been reported worldwide, and none have been seen in Korea.

A 79-year-old male patient visited our department with a six-day history of epiphora and lower lid eversion in both eyes. On slit-lamp examination, lower lid ectropion was present in both eyes, and mild corneal punctate epithelial erosion was also observed. Two weeks after conservative treatment, the lower lid eversion disappeared and the lower lid returned to its original position. No changes were observed three months after treatment. We report a case of acute idiopathic bilateral lower lid ectropion with a literature review.