The deformation failure mechanism of self-piercing riveted structure for ST14 cold-rolled steel and 5083 aluminum alloy dissimilar sheet combination under static loading was studied. Then, the forming quality of steel-aluminum self-piercing riveting was compared and analyzed, and the process parameters were determined. Furthermore, by tensile-shear test, the influences of lap sequence and number of rivets on static mechanical properties, instantaneous stiffness and failure behavior of the joints were analyzed, and the deformation failure mechanism of the steel-aluminum dissimilar self-piercing riveted joints under static loading was investigated. The results show that the forming quality, static mechanical properties and instantaneous stiffness characteristics of the joints with the steel as upper sheet are better than that with the aluminum alloy as upper sheet. The performance of steel-aluminum self-piercing riveted joints can be improved significantly by increasing the number of rivets, and has a better effect on the joints with the aluminum alloys as lower sheet. The static loading failure modes of single-rivet joints are the rivet separated from lower sheet, and the failure modes of double-rivet joints are the rivet separated from ST14 cold-rolled steel lower sheet and the fracture of 5083 aluminum alloy lower sheet, respectively. The upper sheet is deformed after the failure of the joints, and the deformation characteristics are more obvious, and the better bearing capacity can be obtained when taking the better plastic material as the upper sheet. The increasing of the number of rivets can effectively restrain the plastic deformation of the sheet and further improves the bearing capacity of the joints.