A decomposition device for organic substances using ultraviolet rays. The organic substance in the solvent is disassembled by dissolving the organic substance to be decomposed into a solvent and sending it to the light rebellion tank at a certain flow rate. In addition, the decomposed organic substance can be further reacted by catalytic chemicals, which can promote disassembly with low energy. The obtained disassembly can be recycled by separating by distillation as needed.