Abstract:Objective: To observe the effect of Congrong powder preparation on erythrocyte parameter and the index of blood rheology in healthy rats. Method: The 50 rats were randomly divided into 5 groups ( physiological saline group, testosterone propionate group, large-dose administered group, moderate-dose administered group, small-dose administered group). Blood were taken to determine erythrocyte parameter and the index of blood rheology. Result: Congrong powder preparation had no effect on erythrocyte parameter. There was an increase in whole blood viscosity, whole blood reduction viscosity, and in the erythrocyte rigidity index in the large-dose administered group. Conclusion: Congrong powder can influence deformability and some related characters of erythrocytes.