Ni-14Cr-10P metal powder was prepared by vacuum melting and inert gas atomization, and then Ti powder and polymer paste were added and stirred at high speed to prepare Ni-14Cr-10P-xTi paste active solder. The C/C composites were welded in the vacuum brazing furnace with the prepared active solder paste, and then the welded joint shear strength was tested. The microstructure and mechanical properties of the joints were investigated by SEM, EDS and XRD. The results show that the strength of the welded joint decreases with the increase of welding temperature and the holding time；The addition of Ti accelerates the decrease of welding strength with temperature and holding time. Combined with the microstructure, the reason why the welding strength decreases with the increase of temperature and holding time after the addition of Ti element is analyzed.