Abstract: OBJECTIVE To investigate into the effect of Naoliuke Capsule on immune organs and blood rheology of tumor-bearing mice.METHOD Observation was made on the effect of Naoliuke Capsule on the weight of the spleen and thymus of tumorbearing mice and the spleen and thymus indexes using sarcoma S180 model,and on changes of rat blood rheology using W256 tumor cells.RESULT Naoliuke Capsule at different dosages had no marked effect on the weight of the spleen and thymus of tumor-bearing mice and the spleen and thymus indexes,with no statistical significance as compared with the model group(P>0.05).Medium and large dosages of the capsule could reduce whole blood viscosity,plasma viscosity,volume of packed red blood cells and maximum agglutination of red blood cells,with marked difference as compared with the model group(P<0.05,P<0.01).CONCLUSION Naoliuke Capsule has no marked effect on the immune organs of sarcoma S180 model,but can improve blood rheology index of transplanted tumor W256 model rats,suggesting its good effect to activate blood circulation to remove blood stasis.