In the design process of highway projects, applying building information modeling (BIM) technology, using parametric design methods, and delivering complete project models is a challenging task. During the design process, issues such as efficient design workflow, data exchange, model segmentation, WBS info, and digital delivery need to be addressed. With parametric design tools like Dynamo software, engineers can automatically create models and complete property assignments based on project requirements, significantly reducing repetitive work and allowing them to focus more on the design itself. This case study will show you the complete parametric design workflow and data exchange for this highway expansion project, with a focus on parametric modeling using Dynamo and Python. Through parametric modeling via programming, stakeholders can achieve efficiency gains of two to three times compared to manual modeling methods for roadbeds, pavements, bridges, and tunnels.