Abstract: To achieve seamless integration between rebar detailing design and processing in bridge engineering, this paper proposes a parametric modeling-based method for rebar detailing and cutting optimization in prefabricated small box beams. First, Revit and Dynamo software are used for parametric modeling to create models of prefabricated small box beams and their rebar. This modeling process not only integrates various types of rebar models into a unified platform but also dynamically optimizes the beam dimensions and rebar layout through flexible parameter adjustments to meet different design requirements. Once the rebar model is completed, the system extracts rebar attribute information, including diameter, length, and quantity, to generate the corresponding cutting scheme. It then analyzes the total cutting cost to evaluate the economic efficiency of various schemes. Finally, the method was applied to a bridge project in Dongxihu District, Wuhan, where its functionality and practicality were verified through real-world implementation.