Inhibit angiogenesis is one of important tumor therapies. If the mechanism of vascular changes can be detected from molecular lever,it will have therapeutic significance. Raman spectroscopy is a non-destructive spectrum technology holding rich information,which can be applied to the structural analysis of solid,liquid or solution of biological molecules. Based on confocal Raman microscope,a unique system is developed for obtaining the different Raman spectrum about vessels of the chick embryo with and without the anti-angiogenic drugs-thalidomide. In the study,the location and shape of the average Raman spectrum of vessels in drug 5 h is similar to the ones without medicine,but the intensity of some characteristic peaks changes. Intensity at 1441 cm-1,1527 cm-1and 1657 cm-1,increases markedly,while the 971 cm-1 and 1081 cm-1 decreases. The change is due to vascular medicine which causes the nucleic acid,protein,phospholipids and other important biological molecules in the vessels to change on the structure or content.The result indicates that Raman spectroscopy could be an effective tool for detection of the mechanism of vascular changes.