The Fatemi–Socie criterion is evaluated using the combined axial torsion fatigue testing results obtained from extensive experiments on thin-walled tubular specimens made from 304 stainless steel. The Fatemi–Socie criterion combines the maximum shear strain amplitude with a consideration of the normal stress on the critical plane. Rainflow cycle counting and Morrow’s plastic work interaction rule are used to calculate fatigue damage. The fatigue life prediction is conducted by using the maximum shear strain plane as the critical plane by considering the weight function and the maximum damage plane as the critical plane. It is concluded that the results gained by two approaches are both acceptable for the case examined.