Abstract: The effect of the subcutaneous bubble of the cast billet on the surface quality of the wire is not clear. For this reason, the artificial bubbles were preseted on the ML08Al continuous casting billet, and the bubbles were tracked and sampled at different stages of rolling. The results show that the artificial bubbles in the corner of the billet can be inherited to the surface of the wire and cracks with certain depth are formed, while the depth of the crack formed by the artificial bubble in the center inherited to wire surface is very shallow. The length of the cracks evolved from the artificial bubbles on the billet surface grows with the increase of rolling passes, and the depth of the cracks evolved from the artificial bubbles can be calculated according to the formula of the relative crack depth.