Abstract: Ti/Cu/Ti diffusion brazing,which is heated with oxygen-acetylene flame and pressed simultaneously,is realized under protection of the coating.The measurement results of interfacial microstructure,composition and cohesion strength of joint by backscattered electron,energy dispersive spectroscopy and tensile test indicate that full diffusion occurs between Cu and Ti in the joint within the test temperature range.In the temperature range from 840℃ to 870℃,the microstructure consists of Cu₄Ti and Cu (Ti)(solid solution) in the middle part of the joint and the cohesion strength is relative high.In the temperature range from 870℃ to 900℃,the microstructure is composed of CuTi and Cu₄Ti+(Cu (Ti))(solid solution) in the middle part of the joint and the cohesion strength is relative low.The cohesion strength has something to do with heating temperature.