To fabricate a heterostructure solar cell using environmentally friendly materials and low cost techniques, tin oxide (SnO₂) and cuprous oxide (Cu₂O) were deposited by the sol-gel method and the electrochemical deposition, respectively. The SnO₂ films were deposited from a SnCl₂ solution containing ethanol and acetic acid. The Cu₂O films were deposited using a galvanostatic method from an aqueous bath containing CuSO₄ and lactic acid at a temperature of 40°C. The Cu₂O/SnO₂ heterostructure solar cells showed rectification and photovoltaic properties, and the best cell showed a conversion efficiency of 6.6 × 10^－2 % with an open-circuit voltage of 0.29 V, a short-circuit current of 0.58 mA/cm², and a fill factor of 0.39.