By using the scattering matrix method, the properties of two-dimensional electron gas spin polarized transport through step-magnetic barrier structure at different bias voltage are investigated. The results show that (i) the degree of spin polarization is cyclically reducing if the incidence energy increases at zero bias voltage, and (ii) it is reduced slower and the maximum of spin polarization decreases when the number of steps increase in this structure, and (iii) it is enhanced significantly in a wider energy range under applied bias voltage, and more distinct spin-filtering properties are observed in the step-magnetic barriers.