AIM:To discuss clininal effect of microscopic operation shortening levator palpebrae superioris for treatment of moderate and severe congenital ptosis.METHODS:Part of the levator palpebrae superioris of 53 paients(68eyes)who had moderate and severe congenital ptosis was resected in the microscope.RESULTS:Observed for 3 months to 1 year,cure was in 41 eyes and basic cure in 27 eyes of the 68 eyes operated.The satisfactory rate was 100%.All the patiens was satisfied with the microscopic operation.They were good looking and there were no complications.CONCLUSION:The microscopic operation for treatment of moderate and severe congenital ptosis is considered effective with high success rate.