In this study, we report the role of integrin α₅ in promoting melanoma metastasis. The α₅ expression was remarkably elevated in highly metastatic B16F10 melanoma cells compared to lowly metastatic B16F1 cells, whereas no significant changes were detected in those of integrin α₄, α_v, and β₁ subunits. Neutralization of α₅ with anti-α₅ antibody significantly suppressed the potential of B16F10 cells for pulmonary metastasis in mice and inhibited cell adhesion or spreading to fibronectin in vitro. Furthermore, loss of the interaction between α₅ and fibronectin diminished cell survival and induced apoptosis in B16F10 cells. Above results provide clear evidence that integrin α₅ is positively correlated with melanoma metastasis and might be an anti-melanoma target.