The purpose of this article is to analyze the advantages and application paths of BIM5D technology in the cost control of completed houses. In the research phase, based on the reading of literature and the combination of project materials, the advantages of BIM5D in the cost control project of completed houses are analyzed after introducing the cost control of completed houses and the connotation of BIM5D technology. Finally, this article starts from multiple perspectives, including BIM5D modeling, cost deviation analysis under dynamic cost control, etc., and finally forms a relatively systematic and complete BIM cost control technology system. It is hoped that this article can provide technical reference value for China’s completed housing projects, promote the improvement of the project team’s cost control level, obtain considerable economic benefits based on completing project construction with quality and quantity, and enhance the competitiveness of enterprises.