Objective: To investigate the association between increased carotid intima-media thickness (CIMT), homocysteine level, and MTHFR C677T (rs1801133) gene polymorphism in Egyptian people with rheumatoid arthritis (RA). Subjects and methods: 280 Egyptian women (160 RA patients and 120 controls) were included in the study. CIMT was measured using high resolution B-mode ultrasonography and homocysteine levels were measured using enzyme -linked immunosorbent assay. While, MTHFR C677T polymorphism was analyzed by polymerase chain reaction -restriction fragment length polymorphism. Results: We found that subjects who carried the TT genotype and T allele were significantly more likely to develop RA with 2.9 and 1.5 fold, respectively. RA patients carrying the T allele presented a statistically significant increased risk of developing atherosclerosis compared with those carrying the C allele. Moreover, MTHFR TT genotype was independent risk factor of thick CIMT. Conclusions: C677T MTHFR gene polymorphism is associated with RA in Egyptians. MTHFR 6771T carriers had higher concentrations of serum Hcy than did subjects harboring the CC and CT genotypes. The presence of 677T allele increases the risk of atherosclerosis in patients with RA. This increased risk of atherosclerosis could be due to hyperhomocysteinemia. (C) 2017 Elsevier B.V. All rights reserved.