Objective: To study the central corneal thickness measurement in different refractive errors, gender and age group: Methods: This Hospital based, Observational, Cross sectional study was conducted among patients presenting to Department of Ophthalmology, Lady Hardinge Medical College and Associated Hospitals, New Delhi, India(either as outpatient or requiring admission). Duration of study was November 2017 – March 2019. Result: Males had thicker cornea than females. Mean CCT value in male by noncontact pachymetry was 497.82 ± 30.41µm and in females was 491.27 ± 26.34µm but P value was insignificant =0.12.Similarly mean CCT in male by ultrasonic pachymetry was 534.02 ± 31.57µm, and in females was 526.61 ± 27.26µm which also showed insignificant result P =0.10. Hence we conclude that CCT has no statistically significant differences in the two sexes. Mean CCT in myopes was 478.58 ± 25.54 µm by noncontact pachymetry and 516.92 ± 27.19µm by ultrasonic pachymetry which was lower than hypermetropes 491.67 ± 24.95µm (nonpachymetry), 527.15± 26.49µm (ultrasonic pachymetry) followed by emmetropes 497.73 ± 28.43µm (noncontact pachymetry),534.03 ± 28.16 µm(ultrasonic pachymetry). These results were significant as P value obtained was < 0.01.Hence we can conclude that differences of CCT value between two instruments in different refractive error group were significant. Conclusion: CCT has no statistically significant differences in the two sexes. Males showed thicker CCT value than females both by noncontact and ultrasonic pachymetry but the intersex differences were statistically insignificant. CCT values obtained in different age groups had not much difference signifying no change in CCT according to age group but CCT compared between noncontact and ultrasonic pachymetry in different age group with P value obtained < 0.01 which is significant. Differences of CCT value between two instruments in different refractive error group were significant.