The as-quenched (AQ) and after alternating current magnetic field (ACMF) treatment Fe78Si9B13 amorphous ribbons have investigated by XRD, DSC and VSM. The XRD and VSM results show that the nearest neighbor distance (d) and coercivity (Hc) of the ACMF treatment samples first decrease and then increase with increasing alternating current, however, the saturation magnetization varies little with the alternating current. The changes of d and Hc are attributing to the interaction of inhomogeneous characteristics structures in present alloys in the structural magnetic relaxation process. The apparent activity energies, local activity energies and local Avrami exponents of AQ and ACMF treatment samples deduced from DSC curves show that ACMF treatment increased the onset crystallization activity energy and local Avrami exponent and decrease the apparent growth activity energy of the crystallization reactions. The changes of crystallization behavior are ascribe to atomic pair ordering in atomic clusters and diffusion of free volume resulted by the magnetic aftereffect.