The aims of this study were to determine the central corneal thickness (CCT) and corneal curvature (CC) in patients with rheumatoid arthritis (RA), and to evaluate the correlations between the CCT, CC, RA activity, and RA duration. Fifty-four RA patients (104 eyes; 35 with dry eye, 69 without dry eye) and 21 age- and gender-matched control patients (42 eyes) were enrolled in the study. The CCT and CC were measured by ultrasonic pachymeter and autorefractor-keratometer, respectively. RA activity was assessed using the disease activity score (DAS) 28. The independent samples' t test and Pearson correlation analysis were used in the statistical analyses. Mean CCTs were found to be 535.88 +/- 38.24, 530.46 +/- 32.88, 538.64 +/- 40.64, and 543.40 +/- 40.66 mu m in all RA eyes, RA with dry eyes, RA without dry eyes, and control eyes, respectively. Mean keratometry (K) readings were found to be 43.84 +/- 1.76, 43.73 +/- 1.23, 43.90 +/- 1.98, and 43.60 +/- 1.48 D in all RA eyes, RA with dry eyes, RA without dry eyes, and control eyes, respectively. There were no significant differences in CCT values (p values, 0.293, 0.134, and 0.550, respectively) and K readings (p values, 0.435, 0.681, and 0.402, respectively) between the RA and control eyes. These findings led us to the conclusion that the CCT and K readings were not significantly associated with DAS (p values, 0.678 and 0.812, respectively) and RA duration (p values, 0.108 and 0.080, respectively). Our results show that CCTs and CCs were not significantly different between the RA eyes and control eyes. CCTs and CCs were also not associated with RA activity and RA duration.