Abstract: In order to solve the organizational management difficulties of in large-scaled project constructions, this paper develops a BIM-based construction organization assistant decision system by combining the BIM technology and intelligent operation algorithms in areas of engineering construction organization. The design framework of the system and its module functions are also introduced in details in this paper. Applications of the system in practical engineering have shown that the proposed system can be used for scientific planning design and comprehensive systematic verification of the project construction organization scheme.