Abstract: The joints of high purity alumina ceramics and Ti metal with high strength and tightness are needed in electron tube.The joints with shear strength higher than 100 MPa could be achieved by brazing with Ag-Cu-Ti at the temperature of 825-875℃ and the holding time of 15-20 min.Lower or higher temperature and shorter or longer holding time are detrimental to joint strength,and the joint strength decreased when the ceramic surface was abraded.The joint consisted of Al₂O₃/reaction layer/Cu-Ti compounds+Ag/α-Ti,(Cu)/Ti.The main products in the reaction layer were Cu₃Ti₃O and Cu₄Ti.