NOVELTY - A back-panel material comprises composite membrane laminated by layers of membranes and adhered by adhesive. The composite membrane comprises two layers of weather-resistant membranes made of PTFE, fluorinated ethylene propylene, polyvinylidene fluoride, polyfluoroethylene, tetrafluoroethylene-ethylene copolymer, tetrafluoroethylene-perfluoroalkoxy vinyl ether copolymer and/or polyethylene terephthalate; and an intermediate moisture-resistant membrane in between two layers of the weather-resistant membranes, and comprising a base membrane and a thin inorganic oxide layer.    USE - A back-panel material for solar battery component.    ADVANTAGE - The material has superior moisture-resistant performance and durability, excellent insulation; and can prevent electric leakage.    DETAILED DESCRIPTION - A back-panel material comprises composite membrane laminated by layers of membranes and adhered by adhesive. The composite membrane comprises two layers of weather-resistant membranes having a thickness of 5-200 mu m and made of PTFE, fluorinated ethylene propylene, polyvinylidene fluoride, polyfluoroethylene, tetrafluoroethylene-ethylene copolymer, tetrafluoroethylene-perfluoroalkoxy vinyl ether copolymer and/or polyethylene terephthalate; and an intermediate moisture-resistant membrane having a thickness of 30-300 mu m in between two layers of the weather-resistant membranes, and comprising a base membrane and a thin inorganic oxide layer having a thickness of 10-50 mu m. The basement membrane is made of PTFE, fluorinated ethylene propylene, polyvinylidene fluoride, polyfluoroethylene, tetrafluoroethylene-ethylene copolymer, tetrafluoroethylene-perfluoroalkoxy vinyl ether copolymer, and/or polyethylene terephthalate. The thin inorganic oxide layer is obtained by vapor deposition and coating of aluminum oxide or silicon oxide. The basement membrane comprises a thin base membrane having a thickness of 3-20 mu m, and a thick basement membrane having a thickness of 5-200 mu m.