Abstract: Hybridization in breeding of tulip tree(Liriodendron L.) in last 40 years was reviewed.The history since the beginning of hybridization carried out by the late professor Ye Peizhong could be divided into three stages with researches focusing on:hybridization compatibility and heterosis;hybrid trial on growth and adaptability;full development on hybridization.The main achievements included:grasping of hybridization compatibility,hybridization embryology,pollination biology and hybridization techniques;preliminarily figuring out the causes for the heterosis;selecting of elite hybrid families and clones;developing of propagating techniques;establishing extension base and exploring strategy in research and utilization.The paper also presented an outlook for the breeding of the tulip tree.