The purpose of this study was to measure the extent to which complications relating to cataract surgery are a cause of visual impairment in a population aged 50 and over from the city of Campinas, São Paulo State, Brazil. An assessment of cataract surgery services was conducted using random cluster sampling, with the sample composed of 60 clusters of 40 people aged 50 years or older. Of the selected sample of 2,400 subjects, 92.67% were examined. Of these 2,224 examined subjects, 75 (3.37%) presented bilateral visual impairment and 164 unilateral, while a total of 314 (7.06%) eyes presented visual impairment. 352 eyes had undergone cataract surgery. The causes of visual impairment after surgery were concurrent eye disease (56%), surgical complications (28.8%) and refractive errors (15.2%). Cataract surgery complications represented the 5th most important cause of visual impairment. The other main causes were cataract, posterior segment disorders, diabetic retinopathy and glaucoma. These results suggest cataract surgery complications are a major cause of visual impairment in this population. Their prevention and treatment must be part of public health care policies.