We have grown MnAs thin films on (1 1 1), (1 1 0), and (1 0 0)Mn-Zn ferrite substrates by molecular beam epitaxy (MBE) and succeeded in growing epitaxial single-crystalline MnAs films with the growth plane of (0 0 0 1) on the (1 1 1)Mn-Zn ferrite substrates. Atomic force microscopy (AFM) measurements have revealed that the surface of the MnAs epitaxial film is atomically flat. The reflection high-energy electron diffraction (RHEED) and X-ray diffraction (XRD) measurements have shown that the MnAs epitaxial films have in-plane alignment of [1 1 (2) over bar 0]MnAs parallel to[1 (1) over bar 0]Mn-Zn ferrite. On the other hand, polycrystalline MnAs has grown on(1 1 0) and (1 0 0)Mn-Zn ferrite substrates even under the same growth conditions.