Abstract: A prefabricated concrete grid composite wall structure has been developed to address the need for energy-efficient and easy-to-install construction methods for low-rise ultra-low-energy houses in villages and towns. The optimized hexagonal opening grid composite wall, strip sandwich insulation floor, bolted rabbet joints, and connection modes between components are proposed. Through numerical simulation of wall components, the force transfer characteristics and failure modes of the grid composite wall structure and connection joints are studied. In order to improve computational efficiency, a simplified model of the grid composite wall based on shell elements is proposed. In the model, the grid wall is simplified into a homogeneous shell element wall without openings, and the bolts are also simplified non substantively. Parameter analysis has shown that filling the hexagonal openings of the grid wall with thermal insulation materials can achieve the objectives of light weight, material efficiency, cost-effectiveness, and environmental friendliness, while also meeting the bearing capacity requirements of low-rise residential structures in villages and towns. The structural system provides a new option for constructing houses in rural areas.