The ferromagnetic resonance (FMR) technique was used to determine the magnetic anisotropies of the as-quenched and furnace annealed Fe77Cr2Si5B16 metallic glasses. The heat treatment of metallic glasses caused an increase in the effective magnetic anisotropy with the increase of annealing time due to the stress relaxation and than crystallization of the sample. Changing of the magnetic properties such as magnetic anisotropy, magnetic coercivity, susceptibility and magnetic hysteresis loops of the samples were observed for as-quenched and annealed samples. The magnetic hysteresis loops of as-quenched and annealed samples for 1, 2, 4, 6, 8, 10 minutes were measured by Vibrating Sample Magnetometer (VSM) at room temperature and stress relaxations were observed from M-H loops. The value of g-factor and effective magnetic anisotropy constants were calculated from the variation of resonance field with the rotation angle of the samples at out-of-planegeometry. As-quenched and treated samples' g-values were found as 2.19.