Vacuum brazing of TiAl-based alloy to 40Cr steel has been carried out at 1173K for 0.5-40min using Ag-Cu-Ti filler metal. The microstructural analyses indicate that three reaction products, Ti(Cu,Al)2, Ag(s.s.) and TiC, are present in the brazing seam, and the interface structure of the brazed joint is TiAl/Ti(Cu,Al)2 +Ag(s.s.)/Ag(s.s.)+Ti(Cu,Al)2/TiC/40Cr. The experimental results show that the shear strength of the brazed TiAl/40Cr joints decreases as the brazing time increases, and it is up to 175MPa when the joint is brazed at 1173K for less than 2min.