Cancer cells can survive and grow becasue they have tumour vasculature to get blood, nutrients and oxygen. As it is, the tumour vasculature is an attractive target for cancer therapy. Now researchers develop 2 kind of drugs targeting angiogenesis which are VTAs (Vascular targeting agents) and VDAs (Vascular disrupting agents). VTAs(Vascular targeting agents) can prevent new blood vessels from forming with on functions on blood vessels that already feed existing tumors.In contrast, VDAs (Vascular disrupting agents) lead to the vascular structure of a solid tumor to collapse so that VDAs (Vascular disrupting agents) can deprive the tumor of blood and oxygen the tumors need to survive, resulting in tumor ischemia and necrosis. Small molecule vascular disrupting agents including flavonoids, tubulin-binding agents are extremely important for both maintaining tumor growth and controlling the tumor environment.