Before and after the intravenous administration of Ligustrazini, hemorrheology, pulmonary hemodynamics and right cardiac function were studied in 49 patients with advanced cor pulmonale. It was found after one course of treatment that Ligustrazini had the effects of decreasing mean pulmonary arterial pressure and pulmonary vascular resistance, increasing cardiac output and improving right cardiac function and hemorrheologic quality. These findings indicate that Ligustrazini has the effects of vasodilation and improving hemorrheologic quality in advanced cor pulmonale due to chronic obstructive pulmonary disease.