Abstract: Insufficient coordination between the design and construction of building electrical power supply and distribution systems is a critical factor restricting the improvement of engineering quality. To address prominent problems under the traditional mode, including disconnection between design and construction, poor connection between working procedures, and a high rework rate, this paper systematically sorts out key integrated technologies covering multiple links such as load calculation and scheme optimization, equipment selection and layout planning, installation and commissioning of power transformation and distribution equipment, cable laying and cable tray construction, as well as lightning protection and grounding construction. A collaborative management and control system integrating design and construction is established, and a comprehensive evaluation of this integrated mode is carried out in combination with quality acceptance standards and comprehensive benefit analysis. Engineering practice demonstrates that the integrated mode can effectively improve construction efficiency, reduce project costs, and ensure the safe and stable operation of power supply and distribution systems.