PURPOSE. Vitrectomy is associated with the rapid progression of nuclear cataracts. This study was conducted to test the hypothesis that age-related liquefaction of the vitreous gel may also be associated with lens opacification. METHODS. Lenses from eye bank eyes were graded for nuclear, cortical, and posterior subcapsular opacities, and the amount of liquid vitreous was measured. RESULTS. Nuclear sclerosis (NS) grade, percent liquefaction, and age all correlated highly (P < 0.0001). After adjustment was made for age, the correlation between NS and percent liquefaction was 0.37 (P < 0.0001), and the correlation between age and NS after adjustment for liquefaction was 0.57 (P < 0.0001). After the eyes were stratified into age groups, the correlation between NS and percent liquefaction was found to be highest in eyes from donors aged 51 to 70. Cortical and posterior subcapsular opacities increased with age, but scores for these cataract types did not significantly correlate with vitreous liquefaction. CONCLUSIONS. Loss of vitreous gel during aging increases the risk of nuclear cataracts. Preservation or replacement of the vitreous gel may protect patients from nuclear cataract.