We investigated an electrical conduction mechanism of Si/FeSi₂ composite films by measuring a frequency dependence of AC electrical conductivity. The results were analyzed based upon Jonscher’s power law. The hopping conduction obeying the Jonscher’s power law was observed for a-Si single films after annealing as well as Si/FeSi₂ composite films annealed at 550 and 900 °C. From the analysis of XRD, optical absorption, TEM/EDS and AC conductivity, we conclude that the electrical conduction mechanisms in polycrystalline (poly)-Si/β-FeSi₂ annealed at 550 °C and poly-Si/α- and β-FeSi₂ annealed at 900 °C are due to electron hopping via the conduction band of β-FeSi₂ and α-FeSi₂ nanocrystals embedded in poly-Si thin films, respectively.