Background\nThe mechanism of atherogenesis has not yet fully understood despite the different studies in this area. This study aimed to evaluate the role of zinc (Zn)-supplemented with high cholesterol diet (HCD) on the serum and whole blood rheological properties of rabbits fed a HCD. \nMaterials and methods\nTwenty-four New Zealand white rabbits were divided into control, HCD, and HCD + Zn groups. The HCD group was fed a diet with 1.0% cholesterol and 1.0% olive oil. The HCD + Zn group was fed a diet with 1.0% cholesterol, 1.0% olive oil, and Zn. Blood viscosity, shear stress, and torque (%) were measured at shear rates ranging from 225 to 1875 s-1 for serum and 75 to 900 s-1 for whole blood.\nResults\nSerum viscosity and shear stress in HCD rabbits were significantly higher at all shear rates compared to controls; while whole blood viscosity and shear stress in HCD rabbits were significantly lower at all shear rates compared to controls. Viscosity and shear stress in both serum and whole blood from rabbits in the HCD + Zn group returned to normal values at all shear rates.\nConclusions\nThe rheological properties plays important role during the progression of atherosclerosis. The Zn supplemented with HCD to rabbits delays or retards the progression of atherosclerosis. Changes in blood serum viscosity could reflect changes in non-clotting proteins, glucose, nutrients, and trace elements; while changes in whole blood viscosity could result from changes in hematocrit, hemoglobin, and erythrocyte count. One of the factors responsible for increasing the serum viscosity values of HCD rabbits might be attributed to increase in Fe and decrease in Zn levels in blood serum.