We report the epitaxial growth of Cu 2 O (001) and m-plane (101¯0) ZnO/Cu 2 O thin films on both bulk MgO (001) and biaxially textured thin films of MgO (001) via plasma-assisted molecular beam epitaxy. Cube on cube epitaxial growth of Cu 2 O thin films on both bulk MgO (001) and biaxially textured thin films of MgO (001) was observed and confirmed via X-ray diffraction and reflection high energy electron diffraction measurements. In addition, epitaxial m-plane ZnO growth via plasma-assisted MBE was conducted on both MgO substrates and Cu 2 O/MgO substrates. The ability to grow oriented, high-quality n-ZnO/p-Cu 2 O heterostructures enables improved thin film morphology and may have important implications for optoelectronic and photovoltaic devices.