Profile straight seam free thermo-insulating outer door concrete building block

The utility model relates to an exterior wall tile for building engineering, particularly a special-shaped no-straight-seam concrete thermo-insulating exterior wall building block, which is a composite square structure composed of an upper, a middle and a lower layers, wherein the middle layer is composed of a hollow composite concrete outer layer and a hollow interiorly-filled coal ash cement foam inner layer, and the upper and the lower layers are respectively composed of a star-shaped composite concrete outer layer and a star-shaped interiorly-filled coal ash cement foam inner layer, openings of which are oppositely arranged; the upper, the middle and the lower layers are arranged in the mutual superposition mode, the upper layer is arranged right on the lower layer, a longer side and a shorter side along one side of the middle layer respectively retract inward so as to form a groove, and the corresponding side of the groove forms a convex rib the size of which is the same as that of the groove. The utility model changes the characteristics of the brick building block structure, overcomes common defects of traditional building blocks, solves the problem of thermal insulation of walls by utilizing coal ash, and the price is much lower than the expenses of exteriorly thermal insulation exterior walls. The utility model has the advantages of energy saving, long service life of exterior walls, environment beautifying, fast construction, low cost, etc.