The ball stud, a kind of bolt having a spherical head, is widely used as a part of a ball joint in steering or suspension systems of automobiles. Generally, the production process of ball studs consists of multi-step cold forging and screw making. Recently, balls and studs are subjected to a heat treatment suitable for each material, and the shear strength of the ball stud must meet the specifications of the production company. This study evaluated the shear strength of joints by varying the welding current and welding pressure in the resistance welding of ball studs. The shear strength showed the least dispersion and distribution at welding current of 10.3 kA and welding pressure of 3.75 ㎏/㎠.