The cost control content of assembly building project is complex, and it is difficult to guarantee the accuracy in manual mode, but it can be solved with the help of BIM technology, and the rationality of control results can be guaranteed simultaneously. With this in mind, this paper introduces the basic concept and application requirements of BIM technology, and then proposes a cost control strategy. Relying on the strategies in the paper, BIM technology can play a role in helping to do a good job of cost control in the construction of assembly buildings, which is helpful to improve the economic benefits of the project.