Abstract: Aiming at the problems of data security risks, low collaboration efficiency, and insufficient localization adaptation existing in current international BIM software, this paper introduces a 2D-3D integrated design system EWBIM based on an autonomous and controllable BIM platform. By constructing a secure and controllable infrastructure, integrating AIGC intelligent modeling technology, and innovating the 2D-3D linkage design mode, the technical barriers of foreign software are broken through. Practical engineering applications show that the system improves data security, modeling efficiency, and collaborative design by 40% compared with traditional platforms, providing a domestic solution for the digital transformation of the engineering construction field.