In this paper, the linear friction welding test was carried out on TC17 titanium alloy by several different welding parameters. The distribution of the interface temperature during the welding process, was measured by embedding the thermol couple, and the OM and SEM technology was applied to analyze the typical welding defects of the joint, the distribution of the joints’ microhardness under two different parameters was measured. The results showed that a sound welded joint cannot be obtained on account of the insufficient heat input in a=1mm. The interface temperature could reach around the phase transition point in a lower amplitude, however, it can reach up to 1170℃ under a=3mm. Additionally, there were welding defects at the interface, such as holes, residual wear particles, oxide layers and inclusions, local unbonded, at a=1mm. The result of the micro-hardness test showed that the microhardness of the joint weld center under a=3mm was the lowest, whereas it reached the maximum value under a=1mm due to the presence of residual oxides and inclusions.