Affection of the main process parameters(Temperature and Time) on microstructure and properties of Ti（C,N）/Ni interface has been studied by using Cu and Nb interlayer in Vacuum diffusion welding device. Results have shown that interface interlayer did not change and interface microstructure was Cu/Nb layer structure and Cu diffused into Ni with a little when diffusion welding temperature was lower than 1273K. But when diffusion welding temperature was 1523K, interface microstructures were Ni8Nb metallic compound and dispersing deposition CuNi solid solution in the earlier, finally they were transformed into (Ti,Nb)(C,N)+Nb7(Ni,Ti,Cu)6+NbNi3 near Ti（C,N） and NiCu+NbNi8 near Ni. It was clear that Cu was as transition liquid which dissolved Ni so as to forming CuNi transition liquid, so that Nb was dissolved in CuNi transition liquid rapidly. Ti(C,N) can been wetted with creating NiNbCu transition liquid, and then, a little (Ti,Nb)(C,N) solid solution were formed at interface so as to increasing interface combining capability. Interface shear strength may get to 140 MPa.