The Cu2O/CuO/SnO2 transparent pn junction film device with Cu2+ self-oxidation transition layer is prepared via a simple thermal oxidation-sputtering method. There, the Cu2O is prepared via a simple sputtering method, the CuO transition layer is prepared via a thermal self-oxidation method on the surface of Cu2O film, and subsequently the SnO2 film is deposited via the sputtering method on the surface of CuO transition layer. As revealed, the as-prepared transparent photovoltaic device exhibits highly transparency of about similar to 75%, obvious photovoltaic conversion enhancement of about similar to 450 folds than unmodified device, decent stability during 10000 s' cycle, which can be mainly ascribed to the Cu2+ self-oxidation transition layer; there, the appropriate Fermi level and nicer lattice matching can provide a decent channel for charge carrier transport, and the visible light response can improve photo-generated carrier excitation and injection. Additionally, the structure design of Cu2O/CuO/SnO2 can prevent the oxidation of Cu2O to increase photovoltaic stability.