Objective To explore the excipients of puerarin for injection which can cause hemolysis of rabbit erythrocytes and to provide reference for clinical safe drug use. Methods Improved test tube method was used in vitro to evaluate the hemolytic affection of injection component. Results The puerarin for injection could cause hemolysis of rabbit erythrocyte. And the mixture of mannitol and sodium bicarbonate had the same effect. Conclusions The puerarin and the interaction of excipients could be the main causes of hemolysis.