The welding riveting composite connection of Q460 steel/6061 aluminum alloy for construction was carried out by using laser-TIG arc composite heat source, the effects of DC-TIG current on the forming, morphology and mechanical properties of aluminum/steel welding riveting composite joint were studied. The results showed that, when the DC-TIG current is 75~ 115 A, the steel/aluminum welding riveting composite joint samples are well formed, and there are no abnormal cracks, pores and other welding defects in the solder joint and surrounding area; With the increase of DC-TIG current from 75 A to 115 A, the area of unmelted area of solder joint gradually decreases, the welding penetration of aluminum plate gradually grows, the tensile and shear load of steel/aluminum welding riveting composite joint first increases and then decreases, and the maximum value is obtained when the DC-TIG current is 95 A; When the DC-TIG current is 75 A, the steel/aluminum welding riveting composite joint shows button fracture, and the other joints show pull-out fracture; The appropriate DC TIG current is 95 A, when the solder joint is well formed, the welding penetration is 350 mm, and the tensile shear load is 5.52 kN.