Objective: To investigate the effect and influence of the state of cardiac function in portal hypertension. Methods: The function of left ventricle of carbon tetrachloride(CCl4) induced cirrhotic rats and partial portal-vein ligated(PVL) rats was determined by HP type 5500 ultrasonic instrument and portal pressure was supervised simultaneously. Results: The increment of blood volume in CCl4 induced cirrhotic rats was more obvious than that in PVL rats.There was no difference in the extent of increment of portal pressure between the two portal hypertensive rat models.The reason was that cardiac output(CO) was maintained in a fixed range by regulation of heart rate and stroke volume. Conclusion:The necessary factor of maintaince of stable portal pressure is in a fixed range of CO regulated by heart.