Abstract: Diffusion bonded joints were prepared between TC4 and ZQSn10-2-3 with nickel as an interlayer in vacuum.The microstructure of transition joints was investigated by scanning electron microscope and energy dispersive spectrometry.The typical interface of TC4/Ni/ZQSn 10-2-3 joint is TC4/β-Ti/Ti₂Ni/TiNi/TiNi₃/Ni/Cu(Cu, Ni)/ZQSn10-2-3.The optimum parameters were obtained in the condition of 830℃ for 30 min under 10 MPa by optimum experiments.The maximum shear strength was 130 MPa.The results showed the fracture was crystal morphology with a little plastic, and occurred proximity to TiNi₃ intermetallic layer in TC4/Ni side through X-ray diffraction analysis.