Crystallization processes of an amorphous (Fe0.99. Mo0.01)78 Si9B13 alloy induced by mechanical milling and annealing at pressures from O to 7.0 Gpa were studicd. It is found that the milling time needed for the crystallization of the amorphous alloy and its crystallization products are related to the milling intensity. The crystallization products are an α-Fe(Mo, Si) disordered solid solution at a lower milling intensty. while at a higher milling intensity they aare α-Fe(Mo, Si), Fe-Si-B. and Fe2B phases. BY comparing the mechanical crystallization of the amorphous alloy with its high pressure crystallization. it is suggested that crystallization of the amorphous alloy driven by ball milling results from the simultaneous action of local pressure (4-6 Gpa) and local tempterature (600-700K), which are produced by the collision of steel balls. The local pressure decreases the thermodynamic potential barrier of nuclecleation and inereases the diffusion activation energy in the processof mechanical crystallization, Leding to that crystallization of amoirphous alloy is depressed when the crystallization needs a long-rane atomic diffusion and is promoted when the crystallization needs atomie diffusionless or short-range diffusion. The local temperature plays the same role in the mechanical crystallization as the annealing temperature in the thermal crystallization.