The microstructures and mechanical properties of Ti-24Al-15Nb-1Mo alloy under different hot-work processes(forging,hot-rolling and solution treatment)and weldability by tungsten inert gas(TIG)welding of the alloy have been investigated.The experimental results show that,compared with solution treatment,the different hot-work processes affect on the microstructures and mechanical properties of the alloy more markedly.Under forging condition this alloy has lower cold-crack susceptibility and higher mechanical properties of the joint.Decreasing constrain degree of joint,controlling post-welding cooling rate and carrying out post-welding heat treatment in time may be important ways to prevent cold-crack of the joint.