AIM:To summarize the causes and the affection to visual acuity of posterior capsule rupture during phacoemulsification for cataract in order to carry out prophylactic measure.METHODS:A total of 200 cases with age-related cataract(220 eyes) were selected and underwent phacoemulsification and intraocular lens(IOL) implantation routinely.RESULTS:Posterior capsule rupture was in 21 eyes(9.5%) during the operation.It occurred during water separating in 1 eye(0.5%);phacoemulsification in 15 eyes(6.8%);I/A cortex in 3 eyes(1.3%);IOL implantation in 2 eyes(0.9%).CONCLUSION:Posterior capsule rupture is closely related to the conditions of patients as well as the experience and skill of operators.Posterior capsule rupture directly affect the recovery of visual acuity after surgery.It is important for clinical prognosis to identify early and management.