The invention discloses a special metal resistance rivet welding device, which belongs to the technical field of automobile manufacturing. The special metal resistance rivet welding device comprises an piercing electrode, a blank holder, a plurality of spring bead positioning mechanisms, a semi-hollow rivet and an annular electrode, wherein the blank holder, a to-be-welded plate and the annular electrode are arranged in turn from top down; the piercing electrode is sleeved in the blank holder; the plurality of spring bead positioning mechanisms are horizontally arranged in the blank holder along a radial direction; the semi-hollow rivet is vertically arranged in the blank holder and is contacted with the spring bead positioning mechanisms; and the piercing electrode, the semi-hollow rivet and the annular electrode are arranged coaxially. In the invention, based on the mechanical connection of the self-piercing riveting process of the semi-hollow rivet, the resistance heat generation mechanism of resistance spot welding is introduced, the softening of plates by resistance heat eliminates riveting cracks and brittle fractures, reduces riveting force and increases the mechanical locking between the rivet and a lower-layer plate, the soldered connection between the rivet and plate pieces is realized by resistance heat, mechanical-solid phase double connection is formed finally and the reliability and connection strength of an adapter are improved.