Visual impairment and blindness are major complications of diabetes and are regarded as the most serious disability by most of patients. The purpose of the study was to determine the incidence and prevalence due to diabetes-induced visual disability in 1991-1999 in the former Cracow voivodeship with population of 1,245,047 inhabitants. A register of visual disability was established using independent sources of information. On the end of 1999 the register had included 122 diabetics with visual disability--66 women (54.1%) and 56 men (45.9%). The patients with type 2 diabetes predominated--92 subjects (75.4%). The remaining 30 patients (24.6%) had type 1 diabetes. Grade 1 visual disability was diagnosed in 82 subjects (67.2%) whereas grade 2 visual disability in 40 patients (32.8%). Grade 1 visual disability was defined as visual acuity in a better eye < 0.05 and visual field narrowing < 20%. The criteria of grade 2 were visual acuity after correction in a better eye 0.05-0.1 and visual field narrowing 20-30%. According to the register of the Cracow Branch of the Polish Association of the Blind diabetics made up 6.2% of all visual disability cases. In 1991-1999 the incidence of visual disability due to diabetes did not increase significantly. The mean incidence rate was 0.9/100,000 population. However, there was a significant increasing trend in prevalence with mean annual increase of 0.24/100,000 population (95% CI 0.17-0.31/100,000).