NiTi alloy with equal atomic ratio has been widely used in biomedical field because of its excellent mechanical properties and shape memory effect. However, NiTi alloy can be corroded and released harmful Ni2+ ions in human body. In this paper, laser melting was conducted on the surface of the NiTi alloy to enhance the corrosion resistance in simulated body fluid (SBF). The microstructure, phase structure of NiTi alloy modified by laser melting treatment with various process parameters, as well as the biological corrosion properties of the melted layer in SBF solution were studied. The surface physical properties of the molten layer, such as contact angle and hardness were also tested.