Objective To study the plasma D-dimer (DD) level changes in the patients with rheumatoid arthritis (RA), and to analyze its correlation with various clinical indicators. Methods Selected a total of 138 cases of RA patients and 50 cases of normal person as matched group the plasma D-dimer level and the correlation analysis with age, rheuma-toid factor (RF), erythrocyte sedimentation rate (ESR), visual analogue scale (VAS score)and platelet were analyzed. Results The level of D-dimer level in RA patients was significantly higher than that of healthy controls, and the dif-ference was statistically significant (P<0.01);The D-dimer level of high disease activity group and low disease activity group with RA patients were significantly higher than the remission groups of RA patients (P all <0.01); The D-dimer level in high disease activity group of RA patients was significantly higher than the low disease activity group (P<0.01); There were positive correlations between the D-dimer level and the age, ESR, VAS score, RF, platelet in all RA patients (P all <0.01). Conclusion There is high coagulation state in RA patients, so the D-dimer can be used as a clinical nonspecific inflammatory reaction index in patients with RA, and can direct the clinical treatment.