The embodiment of the invention provides a tenon-and-mortise assembly type building block with a decorative surface and a wire-containing pipeline box structure and a wall body, and relates to the technical field of indoor buildings. The building block comprises a building block main body and a decorative panel, wherein each end surface of the building block main body is provided with a tenon or a mortise, the decorative panel is connected to the plate surface of the building block main body, and adjacent building blocks can be connected through tenons and mortises, so that the fixation among the plurality of building blocks is realized. Therefore, compared with an existing indoor assembly type wall building technology, after the building block is adopted for building a wall, secondary decoration is not needed, the building block can be repeatedly disassembled, assembled and used for multiple times, the whole building block is attractive, the total cost per square meter is greatly reduced compared with the logistics and construction price of an existing cast-in-place concrete brick product, the building blocks are connected simply and directly through the tenons and mortises, the decoration technology of building workers is not excessively depended, common users can also directly assemble the building blocks, and the problems that the building workers are increasingly deficient, the building garbage is flooded and causes disasters and the like are solved.