The primary cardiac defect in Congestive Cardiac Failure(CCF) is decrease in intrinsic contractility of myocardium, usually brought on by prolonged pressure and/or volume overload. A wide range of factors may precipitate or aggravate or worsen blood flow conditions leading to the cardiac failure, and hemorheological factors could be one of them. This investigation aimed to study the possible role and association between change in hemorheological parameters and congestive cardiac failure. Parameters studied in this study on 88 patients of congestive cardiac faliure were - whole blood viscosity, plasma viscosity, red cell rigidity, hematocrit, erythrocyte sedimentation rate, fibrinogen, cholesterol, triglycerides and albumin. The patients were categorized in to 2 subgroups on the basis of their clinical history and diagnosis. The first group was, congestive cardiac failure with coronary heart disease and second group congestive cardiac failure with hypertension. There were significant changes in the hemorheological parameters in both the groups. In cases of congestive cardiac failure with coronary heart disease rise in blood viscosity at low shear rate(p<0.0001) was more significant as compared to high shear rate(p<0.01). Increases in plasma viscosity, red cell rigidity, fibrinogen and erythrocyte sedimentation rate were very significant. Among biochemical parameters increase in plasma triglycerides was statistically significant(p<0.01). In the second group, congestive cardiac failure with hypertension, showed marked increase in whole blood viscosity at low and high shear rates. In this group increase in red cell rigidity was most significant as(p<0.0001) compared to other parameters. Increase in plasma viscosity, fibrinogen and plasma cholesterol and triglycerides were also significant. It was found that the regular smokers had higher values of blood viscosity, red cell rigidity(p<0.05), hematocrit(p<0.005) and plasma viscosity(p<0.05) as compared to non-smoker patients in both the groups. There was no significant change in albumin and hematocrit in both the groups as compared to normal controls. The present study highlights the possible role of hemorheological factors along with other physiological factors in congestive cardiac failure