Aim To study the relationships of methylenetetrahydrofolate reductase(MTHFR) gene C677T polymorphism with essential hypertension and arterial compliance. Methods Genotype of MTHFR gene C677T polymorphism was detected by polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) analysis and characterized by electrophoresis and sequencing in 695 patients with essential hypertension and 509 age-matched normal controls.Carotid-radial pulse wave velocity(C-R PWV) and carotid-femoral pulse wave velocity(C-F PWV) was performed. Results In essential hypertension group,the frequencies of TT genotype and T allele were significantly higher than those of control group(26.5% vs 20.6% and 48.7% vs 42.4%,P=0.015 and 0.002).The C-F PWV of people with T allele was markedly higher than that of people with CC genotype(p<0.05),and the C-R PWV of hypertensive patients with T allele was also higher than that of with CC genotype(P=0.001).The C-F PWV of isolated systolic hypertension(ISH) patients with T allele and the C-R PWV and C-F PWV of no isolated systolic hypertension(NISH) patients with T allele were significantly higher than those of patients with CC genotype(p<0.05). Conclusion MTHFR C677T gene polymorphism may be related to increased risk of essential hypertension,and the 677T allele in MTHFR may be a genetic factor of arterial stiffness in hypertensive patients.