The present invention discloses a hard foamed polyurethane composite plate and its production process. It is characterized by that a layer of polymer sheet material is respectively added on the upper surface and undersurface of hard foamed polyurethane layer, in the interior of polymer sheet material a layer of non-woven fabric is set. Its production method includes the following steps: firstly, preparing polymer sheet material: mixing adhesive and inorganic powder material, making the mixture and non-moven fabric be passed through polymer sheet material production line to produce polymer sheet material; then utilizing polyurethane foaming machine continuous production line to make polyisocyanate and combined polyether be foamed into polyurethane plate material, at the same time making polymer grout sheet material be adhered on two surfaces of polyurethane plate material so as to obtain the invented polyurethane composite plate.