Stress assessment in the steel constructions is crucial for risk mitigation. NDT methods are widely used in such applications. However, many of these methods are hazardous, due to the radiation or chemicals used. The proposed magnetoelastic method is neutral to the natural environment. In this paper, development of such a method of stress assessment in constructional steel samples is presented. Measurements of the magnetic hysteresis loops of the sample members were performed under varying mechanical load on the specially designed steel truss test stand, which allowed to obtain magnetoelastic Bm(Ï)Hm characteristics. The results confirm the feasibility of the new method of NDT stress assessment in the steel truss constructions.