Purpose.To describe the differences of corneal endothelial cell densities, cell size variability and cell hexagonality in cataract populations of south Asia between sexes and ethnic groups.Methods.1,235 eyes of 1,235 male and female patients 40–75 years of age with senile cataract were examined with non contact specular microscopy with semi-automated analysis technique. The cell data of the study population was analyzed in relation to age, sex, and ethnic groups. Mean arithmetic differences and the coefficient of variation of repeated observations were calculated to estimate precision of the technique utilized. The main outcome measures were corneal endothelial cell density, cell size variability and cell hexagonality.Results.The mean corneal endothelial cell density was 2,720 cells/mm2, mean cell size variability was 37.8% and percent cell hexagonality 40%. We found statistical significant difference between the three ethnic populations in all the corneal endothelial cell measurements (p< 0.0001). Females had a 2.9% greater cell density than males (p= 0.0001). There was no significant difference in mean cell density according to age. Variability of cell size, however, increased with age (p< 0.001). These findings were consistent across the three ethnic groups.Conclusions.In a total sample of 1,235 eyes distributed evenly in three cataract patient populations of south Asia, we found statistically significant differences of corneal endothelial cell densities of cell size variability and cell hexagonality between sexes and ethnic groups.