Polyurethane cold storage sandwich panels are moisture-proof and waterproof. It is a hydrophobic material in essence, which eliminates the phenomenon that the thermal conductivity is affected by heat absorption and the occurrence of water seepage on the wall; it has strong thermal insulation performance, extremely low thermal conductivity, excellent processing performance, and is still all thermal insulation materials at present. The one with the lowest thermal conductivity among them not only has excellent thermal insulation performance, but also has good freeze-thaw resistance and sound absorption performance. So it is very suitable for greenhouse to use.