of a ratio of shear plane a ratio of u03b1 u2032 phase is preferably controlled within a range of 1 30 preferably 10 20 under conventional fine blanking conditions in order to realize 100 shear plane ratio additionally the value md 30 is determined within a range of from u2212 60 to u2212 10 to generate u03b1 u2032 phase with a proper ratio suitable for realization of 100 shear plane ratio softness of the austenitic stainless steel is well balanced with the effect of the strain induced martensite u03b1 u2032 phase on the quality of the fracture plane so as to suppress occurrence of drooping thus a blanking plane is improved in dimensional accuracy and die life is prolonged the proposed austenitic stainless steel contains various alloying components at predetermined ratios as follows c and n are components effective for adjusting stability of an austenite phase however excessive addition of c and n makes the austenite phase harder due to solution hardening and also makes a strain induced martensite phase harder the hardening causes increase of blanking load and short life of dies therefore a ratio of c 1 2n is controlled at 0 060 mass or less si is an alloying component added as a deoxidizing agent at a steel refining step excessive addition of si makes an austenite phase harder due to solution hardening and degrades blankability of the stainless steel in this regard an upper limit of si content is determined at 1 0 mass mn is an alloying component effective for stabilizing the austenite phase and improving.