Taking Huaian Baima Lake Bridge as the object, this paper carries out the implementation of BIM technology in the construction of complex heterogeneous steel structure bridge. Meanwhile, BIM technology is deeply integrated with the deepening design, processing and manufacturing, and site construction of steel structure bridge in this paper. In the deepening design stage, 3D coordinate method and Tekla software are adopted to realize the rapid and accurate modeling of space special-shaped steel arch structure, and its efficient drawing is made based on CATIA software. In the processing and manufacturing stage, digital processing technology is used to cut parts, effectively reducing the number of field openings by about 57%; "one plate, one tire" technology with project characteristics is developed for controlling the manufacturing accuracy of curved plate within 2mm. In the site construction stage, this paper proposes optimizing the original construction scheme of "arch before beam", which saves 6.081 million CNY in installation and demolition costs. Constructing management system of Baima Lake project is established at this stage to achieve the real-time, dynamic and comprehensive control of project management and achieve the goal of fine management.