A three-dimensional (3D) parametric modeling method is proposed for structural design, combining a design logic-based modeling approach with a parametric modeling approach. By utilizing the linking mechanism of CATIA V6 software, the structural design hierarchy and 3D modeling hierarchy are unified, reflecting design relationships through model associations among 3D features to form a layer-driven 3D model. The user-defined feature-based parametric method addresses the stability limitations of traditional modeling methods while enabling batch control of design objects through parametric tools, significantly improving design efficiency. Furthermore, this method has been applied to the structural design and preliminary design calculations for a ship’s cargo hold, with results being validated. The presented method can provide references for the 3D structural design of other ship types.