AIM: To investigate effects of salvia miltiorrhiza injection on acute myocardial ischemia and hemorheology. METHODS: The acute myocardial ischemia model and blood stasis model were established with high dose adrenaline subcutaneous injection and being socked in ice water. The effect of salvia miltiorrhiza injection on the electrocardiogram J point and T ware of acute myocardial ischemia and the hemorheology of rat blood stasis model were observed. RESULTS: As compared with model groups, middle and high dose groups of salvia miltiorrhiza injection could obviously inhibit the rising of J point and T wave of the ischemic electrocardiogram, all dose groups of salvia miltiorrhiza injection could prevent the ascending of blood viscosity and fibrinogen and hematocrit. CONCLUSION: salvia miltiorrhiza injection can effectively decrease blood viscosity and improve circulatation of coronary artery, and protect ischemic myocardium.