The ability of tumor cell to adhere and migrate is closely related to metastasis. Cell adhesion molecules, such as selectins, integrins, Ig superfamily and cadherins mediate cell-to-cell and cell-to-matrix interactions. Cell adhesiveness changed by the different expression or distribution of cell adhesion molecules on tumor cell surfaces affects the metastatic potential directly or indirectly, so it is very important for tumor cells to separate from primary lesion and lodgement. Tumor cell migration is thought to be a major limiting step in metastasis. In general, the ability of tumor cells to migrate in vivo or in vitro is positively correlated with their metastatic potential. Once stimulated by motile factor, tumor cells can promote their migration by themselves through chemotaxis and haptotaxis, the molecular mechanism of which is unclear at present yet.