In order to solve the multiple technical difficulties of traditional design, based on the Qingjiang Municipal Large Bridge project as the background, BIM parametric modeling is used to flexibly adjust design parameters and update the model in real time to better adapt to the terrain, geology and structural safety requirements; Through the component collision detection function, spatial conflicts in the design can be discovered and resolved in a timely manner to avoid rework and errors in construction; by utilizing BIM's two-dimensional drawing and precise calculation of engineering quantities, the efficiency of design and drawing can be improved to ensure the accurate procurement and use of construction materials. The results show that BIM technology significantly improves design accuracy and construction efficiency, and reduces project costs and time consumption. The results can provide references for a wider range of engineering construction field.