Abstract: To reduce the repeated work by avoiding from spawning redundant data for reduplicate design in building engineering,a five-layer data model is introduced to reorganize the design information.Based on design reuse theory and the constitution characteristic of the building engineering information,leaves in the hierarchical tree are abstracted from sheets of the blueprint according to reusable properties and are assembled back into sheets via the tree structure,which improves the efficiency of storage and data processing.With the model,a system is developed for defining,searching and assembling the reusable parts,which is suitable for large scale of data from practical project and shortens the period of design.