The modular fully assembled prefabricated concrete structure residential system treats a single dwelling as a prefabricated unit, which is then horizontally spliced together to form a residential floor. Each prefabricated unit includes its walls and upper slab, with the splicing part of the prefabricated wall equipped with a single-layer steel mesh, and the wall thickness taken as half of the standard thickness. Adjacent half walls and the upper half beams above wall openings are connected laterally using distributed bolts, and the lateral splicing and longitudinal connection of cantilevered half beams also employ bolt connections. The vertical connection between each residential floor is achieved by setting connectors at the bottom of the unit walls and splice walls, ultimately forming a residential building. This achievement involves two invention patents: 'A connection system for fully assembled prefabricated concrete structures' (201210052417.3) and 'A unitized fully assembled prefabricated concrete structure residential system' (201210052419.2).