Abstract: The process of Mo alloying was performed on the surface of TiNi alloys by double glow plasma surface alloying/metallurgy (DG-PSM) technology, and the cross-section and surface morphology of alloying sample were characterized by means of optical microscopy (OM), glow discharge spectrometer (GDS) and scanning electron microscopy (SEM), and the surface hardness, bonding strength and tribological properties of alloying sample were tested by microhardness tester, durometer, reciprocating wear instrument and white light interferometer. The results show that the alloying layer consisted of triple layers structure after Mo alloying on TiNi alloy surface. From the surface to the matrix, they were Mo deposition layer, Ti-rich alloying layer and Mo-poor alloying layer, respectively. The metallurgical bonding between alloying layer and the matrix was obtained, and the surface hardness and wear resistance of the alloying layer were 2.5 times and 2 orders of magnitude higher than those of matrix alloy.