At present, based on 2D drawings, the project budget usually gets final data through model reconstruction, summary and calculation.The project budget often begins from the stage of drawings and engineering design decisions often ignore the economic rationality.This article aims to find out the mode to connect BIM model with the common cost software, to realize that designers can participate in cost control, to eliminate the work of building model for engineering cost calculation, to improve work efficiency, and meanwhile to explore the rich information of BIM model.