High-quality Fe3O4 thin films have been fabricated onto metallic underlayers of Cr/Cu and Al by rf-magnetron sputtering at low substrate temperatures (<573 K). The measured saturation magnetizations Ms are 462 emu/cm3 for Al (50 nm)/Fe3O4 (200 nm) and 422 emu/cm3 for Cr (45 nm)/Cu (300 nm)/Fe3O4 (200 nm), which are markedly enhanced compared with that for the reference sample deposited directly on a glass substrate, and practically comparable to the bulk value of 477 emu/cm3. Highly conductive transport with an order-disorder change of the Verwey transition was observed in the current-perpendicular-to-plane geometry. The order of decrease in coercive field was achieved by exchange coupling with an overlaid NiFe layer.