Nickel-titanium alloy wires are widely applied in manufacturing biomedical devices; however, it is difficult to be micro-fabricated. Chemical etching process can successfully micro-fabricate the Ni-Ti alloy. The surface morphology, the etching products and the mechanical properties of the fine NiTi wires after the chemical etching process are investigated in the paper. After etching process, the characteristics of the wire surface are studied by Scanning Electron Microscopy (SEM). The X-Ray Diffraction (XRD) phase identification analysis is used to identify the etching products on the side surface of the etched wire. The Vickers Micro-hardness Test shows that the micro-hardness in peripheral surface is slightly higher than that in bulk. Mechanical properties of NiTi alloy fine wires after etching were studied by means of tensile tests.