The results of magnetoelastic tests of hardened and tempered samples of high-chromium 30Kh13 steel, which after magnetization were subjected to low-cycle stretching, are presented. The tests were repeated with a sequential increase in the load amplitude. Stretching on the first cycle led to irreversible demagnetization of the samples. As the number of cycles increases, a quasi-reversible change in magnetization is established, called the piezomagnetic effect of residual magnetization. High sensitivity of specified effect to fatigue loads is established, active change of its sign occurs in vicinity of endurance limit. Keywords: 30Kh13 steel (AISI 420), piezomagnetic effect, residual magnetization, cyclic tests, magnetoelastic demagnetization.