The invention discloses a treatment solution for reducing the oxidation films on the surfaces of copper and copper alloys and a treatment method thereof. In the treatment solution, one or more of ascorbic acid, hypophosphite, glucose, hydrazine, hydrazine derivatives, hydroxylamine and hydroxylamine derivatives are used as reducing agents to reduce the oxygen element in the oxidation films formedon the surfaces of copper and copper alloys and keep the copper element. The treatment solution has the following advantages: the acid fog with a lot of H2, NO2 and the like can not generated in the reduction treatment to seriously influence the fitness of the operator; and after treatment, the copper ion content of the treatment solution is less than 0.5mg/l, thus the water treatment system can not be polluted; and the treatment solution is environmentally-friendly. In addition, the oxidation films formed on the surfaces of copper and copper alloys can be reduced to bright copper and copper alloys in only 1-5 minutes, thus the treatment solution is the treatment solution with low cost,, high treatment speed, remarkable effect and environmental friend and has good market application prospect, and the method is convenient to use.