Abstract:To change the situation that the normal constraint-based parametric modeling method is complex, and the modeling efficiency is low, which is difficult for users to master, a parametric steel joint system based on operation was designed. The difference between operation-based parametric modeling and constraint-based parametric modeling in modeling method, system development and the underlying logic was discussed. The principle of operation was introduced. How to write the logical information into the parametric joint was studied and using industry foundation class(IFC) file to save the joint was realized. Operation-based parametric modeling and non-parametric modeling are basically consistent in the modeling method. Compared with constraint-based parametric modeling, operation-based parametric modeling’s efficiency is improved, the parametric information is able to be shared, and the redundant work of developing the similar joints is reduced. At last, the advantages of operation-based parametric system were introduced by examples.