Abstract: Based on the martensite magnetic characteristics, the deformation-induced martensite contents distribution rule of the cold formed austenitic stainless steel cover shell were studied, and the main influence factors of austenitic stainless steel deformation-induced martensite content were analyzed. The results show that the deformation-induced martensite content was different at different parts of the cover shell. The deformation-induced martensite content at the straight edge zone of the cover shell was the most, that at the transition zone was the second, and that at the spherical zone was the least. The deformation-induced martensite transformation related to the chemical compositions, deformation rate and other factors. At last, measures to reduce the deformation-induced martensite content of the austenitic stainless steel cover shell were proposed.