(111)- and (100)-oriented Fe₃O₄ films were epitaxially formed on a-A1₂O₃(0001) and MgO(100) single-crystalline substrates, respectively, by reactive evaporation method. The formation ranges of the epitaxial Fe₃0₄ films were determined as a function of substrate temperature, oxygen partial pressure, and a deposition rate. Their crystalline qualities were examined by various methods such as X-ray diffraction, RHEED and resistivity mesurements. A lattice mismatch of about 0.3% between Fe₃O₄ and MgO was very small. Then the film deposited on MgO seemed to have a good crystallinity and a smooth surface. Moreover the Verwey transition was clearly detected by a resistivity mesurement at about 110K. The transition temperature was nearly consistent with that of the bulk, indicating a good stoichiornetry of the sample film.