Ion beam induced epitaxial crystallization of amorphous NiSi2is reported. Epitaxial NiSi2layers on (111) Si substrates were implanted at ∼−196 °C with low‐energy Si ions to form an amorphous surface layer. The recrystallization of amorphous NiSi2was induced at 13–58 °C by irradiating with high‐energy Si or Ne ions. Recrystallization proceeded in a layer‐by‐layer manner from the original amorphous/crystalline interface with an activation energy of 0.26±0.07 eV.