Abstract: Parametric forward design constitutes a significant application scenario of BIM technology and represents a continuously evolving technological approach in architectural design tools. As a type of building with relatively high standardization, metro entrance possess the conditions for parametric forward design. The article introduces the parametric design process based on the Revit platform. Initially, by analyzing the pain points encountered in actual engineering projects, the factors influencing the design schemes of metro entrance are distilled. This process subsequently synthesizes the parametric requirements for forward design. Subsequently, the parametric requirements for forward design are determined.Based on a thorough understanding of the underlying logic of the software platform, define the core associated parameters and type parameters in the software. Additionally, the nesting relationships among family models are clarified, appropriate custom families are selected, and a multi-layered nested parametric model is established. Finally, it is necessary to input varying parameters to verify the capability of correctly driving real-time parametric variations in the three-dimensional model. During this process, the constraint conditions are constantly modified to enhance the reliability of the parametric model and apply it to practical engineering. This process offers a viable workflow for parametric forward design, enhancing design efficiency and expanding the application scenarios of BIM technology.