The invention relates to a heat insulation brick for a wall body. The heat insulation brick comprises a first brick body, a second brick body and a heat insulation block, a first bump is arranged at one end of the first brick body, a second bump is arranged at one end of the second brick body, both the first bump and the second bump are provided with a groove, and the heat insulation block is provided with a locating strip matched with the groove. The heat insulation brick has the advantages that the locating strip and the groove are matched to locate the horizontal plane of the first bump onthe heat insulation block and locate the horizontal plane of the second bump on the heat insulation block, a first connecting part and a first slot are matched to locate the vertical plane of the second brick body on the first bump, a second connecting part and a second slot are matched to locate the vertical plane of the first brick body on the second bump, so that no gap exists between the firstbrick body and the second brick body, the heat insulation brick achieves the heat insulation property of the heat insulation brick, the heat insulation brick does not incline when piled up, and the heat insulation brick is simple in overall structure and is convenient to locate.