Aim: We aimed at improving the corneal function in patients with dry eye disease by studying the effect of dry eye disease and its severity on the cornea. Materials and Methods: This study was a case-control, cross-sectional study, that included 200 eyes of 100 patients they were divided into two groups: Group 1: 50 patients with dry eye disease which then divided into (mild, moderate, and severe) and Group 2:50 patients as a control group. Results: The endothelial cell count (cell density) showed a statistically significant difference between the two groups. It was lower in the dry eye group than in the normal group (p=0.005). The central corneal thickness (CCT), co-efficient variant (CV), and hexagonality (HEX) showed no significant difference between the two groups. Conclusion Dry eye disease group showed a decrease in the CD. There was no effect on CCT, CV or HEX. Severe dry eyes showed less CCT and CD than eyes with mild and moderate degrees of dryness. They showed higher HEX than that of mid and moderate dryness. But there was no difference in CV between the three degrees of dry eye disease.