Compact and firm thermal insulation wallboard

The utility model discloses a compact firm type heat preservation wallboard which comprises a middle heat preservation layer and outer layer wallboards on the two sides, the middle heat preservation layer and the outer layer wallboards on the two sides are bonded, the inner sides of the outer layer wallboards on the two sides are each evenly and correspondingly provided with a row of rectangular grooves, and the two sides of the heat preservation layer are evenly and correspondingly provided with a row of rectangular protruding strips. The outer sides of the outer layer wall plates on the two sides are each provided with a layer of decorative plate in an adhesive mode, the outer sides of the outer layer wall plates on the two sides are each correspondingly and evenly provided with a row of sawtooth-shaped protruding strips, the inner sides of the decorative plates are each correspondingly and evenly provided with a row of sawtooth-shaped grooves, and the sawtooth-shaped protruding strips are matched with the