The sensitivity of anti-CCP antibodies for RA was 63.2% and the specificity was 95.0%. The respective values of RF were 59.1% and 91.2%. When considered simultaneously, the AUC for anti-CCP antibodies was 0.90 with a 95% CI of 0.87–0.93 and the AUC for RF was 0.71 with a 95% CI of 0.64–0.77. The presence of both antibodies increased specificity to 98.2%. Anti-CCP antibodies were positive in 34.9% of RF-negative RA patients. Anti-CCP antibodies exhibited a correlation with the radiographic joint damage (Spearman correlation coefficient r = 0.27, P = 0.001). Anti-CCP-positive RA patients had increased the swollen joint count and serum CRP concentration compared with anti-CCP-negative RA patients (Mann–Whitney U test, P = 0.01 and P < 0.001, respectively). However, no correlation was found between anti-CCP antibodies and the DAS28 score (r = 0.13, P = 0.12). RA patients with high anti-CCP2 antibodies (>100 IU/ml) were more likely to have extra-articular manifestations.