The invention discloses an environment-friendly light weight decorative heat insulation board, which is prepared from the following raw materials in parts by weight: 10 to 20 parts of waste glass, 8-14 parts of construction waste, 7-12 parts of closed-cell perlite, 5-10 parts of polyethylene, 9-16 parts of iron tailings, 10-20 parts of cement, 5-11 parts of epoxy resin, 12-26 parts of bentonite, 6-12 parts of calcined kaolin, 3-6 parts of polyester fibers, 2-5 parts of zirconium silicate, 2-4 parts of tungsten carbide, 1-3 parts of aluminum oxide, 2-3 parts of glass fibers, 4-8 parts of modified longan shell powder, 2-3 parts of foaming agent and 2-4 parts of active agent. The environment-friendly light weight decorative heat insulation board is scientific and reasonable in formula; the prepared product is good in heat insulation effect, low in heat conductivity coefficient, and high in breaking strength and shock strength.