This paper discusses the stress dependence of the magnetizing properties of non-oriented (NO) electrical steel sheets. Compressive stresses deteriorate the magnetic properties at low flux density, but improve them at high flux density, where magnetization rotations are induced. Tensile stresses reduce iron losses in all types of sheets, i.e., 50A290, 50A470, 50A1300, and SPCC, at low flux density and those of high-grade 50A290 and middle-grade 50A470 at high flux density, but iron losses of low-grade 50A1300 and SPCC increase at high flux density. These stress dependences may depend on magnetization behaviors (domain wall displacement and magnetization rotation) and magnetostriction. Domain wall displacement mainly occurs at lower flux density, where tensile stresses improve magnetic properties and compressive stresses deteriorate them because magnetic domains that orient the magnetization to ‹100› and λ100 are positive. However, magnetizations rotate to exciting directions at high flux density, with the result that the ‹111› component of magnetization is induced. Here, compressive stresses improve magnetizing properties because λ111 is negative, whereas tensile stresses decrease the iron losses in 50A290 that has large and 50A470 that has middle crystalline grains and increase the iron losses in 50A1300 and SPCC that have small crystalline grains. Therefore, the stress dependences may be modeled by magnetization behaviors, magnetostriction, crystalline grain size, and analysis of the magnetic properties using this model of stress dependence may improve NO steels and their applications.