Obesity is associated with atherosclerotic risk factors, including reduced blood flow, endothelial dysfunction, lipid disorders and hyperinsulinemia. In recent years, several studies have demonstrated that elevated homocysteine is a risk factor for atherosclerosis. This study was aimed at determining whether any relationship between plasma viscosity and homocysteine levels in patients with normo and hyperinsulinemic obese patients. Obese women (n = 75) and healthy, age-matched non-obese women (n = 70) was included in our study. Plasma viscosity, tHcy, insulin level, total-C, LDL-C, HDL-C, triglyceride and glucose level were significantly higher in obese subjects than in non-obese subjects. Obese subjects were also divided into two groups, according to the basal insulin levels as normo and hyper insulinemic. Hyperinsulinemic obese subjects had significantly higher PV level compared with normoinsulinemic subjects. When correlation analyses were performed normoinsulinemic obese subjects, significant correlations were found between PV and total-C (r: 0.776) and insulin level (r: 0.752), BMI (r: 0.580), HOMA-IR (r: 0.510). PV was positively correlated with total-C (r: 0.485), insulin level (r: 0.624), BMI (r: 0.624) and HOMA-IR ratio (r: 0.707), in hyperinsulinemic obese subjects. Hcy was positively correlated BMI in both groups. In conclusion that, it is point out that elevated homocysteine and increased PV are two factors that may act separately and probably do not affect each other.