Abstract: Data transformation among different ship CAD software is a highly concerned issue，with the transformation between CATIA and TRIBON being a particularly important element. By analyzing the structure of model data，a data transformation method from CATIA to TRIBON for naval ships was proposed in this paper. Firstly，the secondary software attached to CATIA was developed to extract its geometry and attribute information，and the precision of this extraction procedure directly determines the overall accuracy of the transformation process. Next，the plug-in software was used to merge the data into a single file and translated it into a valid TRIBON document format. Finally，the remodeling modules of TRIBON were developed to accomplish the transformation. Simulation results show that the proposed method can be used to transmit data among different CAD software effectively and efficiently.