The invention discloses a joint welding method and device. The joint welding device comprises a support, wire feeding devices, a welding gun and a negative pole piece. The wire feeding devices, the welding gun and the negative pole piece are directly or indirectly fixed to the support. The wire feeding devices are used for conveying welding wires to a heat generation area between the welding gun and the negative pole piece. The welding gun and the negative pole piece are jointly used for melting the tin wires. The joint welding device has the beneficial effects that heat generated by an argonarc welding current replaces an electric soldering iron for melting the tin wires, argon arc welding is combined with soldering iron tin wire welding, and the welding effect is better.