Abstract: Ti₃Al-Nb(Ti-13Al-24Nb)and TC4(Ti-6Al-4V) alloys were brazed in vacuum furnace by using 50Ti-20Zr-20Ni-10Cu brazing powder.The brazed joint with different clearances were obtained through contolling the assembly gap.The microstructure and property characteristics of the joint were investigated by using scanning electron microscopy,energy dispersive spectroscopy,electron probe and tensile test.The results showed that the microstructures and properties were remarkably affected by the clearances.When the clearance increased,the microstructures of the brazed joint became complex and the eutectic structure and compound strip coexisted in the brazed joint which is harmful to the strength of the brazed joint.