A copper oxide thin film was synthesized through a copper sheet annealing process that was carried out using a gas stove, furnace and 1000 W tungsten . The product and its response were measured using a and then characterized by XRD, SEM and EDX. Furthermore, the copper oxide was applied as a photocathode in a cell with Platinum (Pt) as the anode for methyl orange degradation, and the thin film annealed at 60 sec produced the highest current density. According to XRD and EDX results, copper oxide structure was dominated by Cu2O, while SEM showed the presence of a Cu2O porous surface. Methyl orange solution degradation also showed the best result for the copper oxide annealed at 60 sec and in all pH variations, while the best degradation was obtained at pH 1.