AIM:To analyze the causes and preventive measures of poor vision after Phacoemulsification (PHACO) operation. METHODS: Data of cases with poor vision after operations from 998 patients with PHACO during 2008 to 2010 in our hospital were collected and analyzed. RESULTS: All cases were followed up for 3 months after operation, there were 130 cases with vision less than 0.3, which was accounted for 13.0% in all cases. CONCLUSION: The poor vision after PHACO was mainly due to original eye diseases, which were senile macular degeneration, diabetic retinopathy, optic nerve injury with glaucoma etc.