Abstract: A novel welding process of transient liquid phase (TLP) diffusion bonding was used to join wireline core drill rod.Mechanical tests showed that the failure of the tensile sample was in the 45MnMoB and the bending degree is 180°, which exceeded the technical criterions of geological drill rod.There was no reinforcement inside and outside the rod.The rod failed while the joint was fine during torsion test, and the torsion strength was higher than that of screw connection.Therefore, the TLP bonding can be successfully applied for joining core drill rod.