Aim To study the significance of the variations of plasma haptoglobin （Hp） in AMI patients. To discuss the correlation between the level of plasma Hp and the coronary stenosis degree in AMI patients. Methods 98 AMI patients were enrolled in this study and 90 healthy persons were selected as control. Detect plasma level of Hp study the difference of plasma Hp level between AMI group and control group. Analyze the correlation between plasma level of Hp and the counts of coronary stenosis as well as Gensini’s score in AMI group. Results Plasma level of Hp in AMI patients were significantly higher than the level in control （P<0.01）. The plasma level of Hp in AMI patients with double branches or three branches stenosis were significantly higher than the plasma level of Hp in AMI patients with single branch stenosis （P<0.05）. The plasma level of Hp in AMI patients with Gensini’s score>30 were significantly higher than the plasma level of Hp in AMI patients with Gensini’s score<30 （P<0.05）. Plasma level of Hp in patients with AMI were significantly and positively correlated with their Gensini’s score. Conclusion There was some correlation between the increase of the level of Hp and the development of AMI. There was some correlation between the plasma level of Hp and coronary stenosis degree in AMI patients.