Objective To examine the changes of blood cells and hemorheology in male uricase-deficient rats (Kunming-DY rats) to improve and perfect its biological data. Methods Compared with male wild-type SD rats of the same age, serum uric acid(SUA) in uricase-deficient rats of 45-day age was determined using the phosphotungstic acid method. Their weight, intake and excreta were recorded. Their tail blood was collected in which the blood cells were analyzed by an automatic animal blood cell analyzer, and 21 results were obtained. The blood from their abdominal aorta was drawn whose 23 hemorheological indexes were analyzed by an automatic animal blood rheometer. Results The SUA level, intake of water and urine volume of uricase-deficient rats of 45-day age were significantly increased. The number of white blood cells decreased with the proportion of lymphocytes increasing, and red blood cell volume decreased along with platelet volume decreasing. In addition, several hemorheological indexes were improved. Conclusion The uricase-deficient rats are prone to infection, nutritional anemia, and "anemia" characterized by small cell low pigment. The platelet function is more mature, which is conducive to hemostasis, and the blood viscosity is also reduced.