Abstract: Double-sided cold arc MIG welding of TA2 Ti and 5A06 Al alloy was carried out with SAl 5183 welding wire. The microstructure characteristics of Ti/Al interface in different thickness direction were analyzed and the tensile strength of the joint was tested. The results showed that the bonding interface between titanium and weld was sharp and clear, no porosity and cracks were found near the interface. Under the influence of welding heat input, two different Ti/Al interfaces were formed: a Ti_3.3Al layer and a TiAl₃ layer were formed between titanium and weld in the upper part of the joint, only one dentate layer was formed in other parts of the joint. The joints were mostly fractured near the Ti/Al interface during tensile test. The ultimate tensile strength of the joints was 355 MPa.