The invention discloses a processing method of a novel light energy-saving environmental-protection board, belonging to the field of processing professional technology of building wall body material; the basic technical proposal is that: the novel light energy-saving environmental-protection board is manufactured by the waste polystyrene foam, industrial production waste coal cinder or coal ash, building-removal waste residue, industrial production waste desulfuration gypsum, low-alkali sulphate aluminium cement, special chemical additive and water by weight parts, wherein the special chemical additive is prepared by radiating polyvinyl alcohol, polyacrylic acid, methylcellulose, lignin and boric acid which have a certain weight parts by Co-gamma rays; compared with the traditional wall body material, the novel composite molding board has the advantages of low cost, temperature insulation, energy saving, high-intensity shock resistance, sound insulation, moisture proofing, durability, light weight, simple manufacturing process, convenient construction, and being capable of fastening hangers, is completely accordance to the national green development requirements of energy saving, environment protection and waste utilization, therefore, the processing method of the novel light energy-saving environmental-protection board is an ideal sustainable development green wall body material.