Under the reform of the camp, BIM technology plays an essential role in the actual work. BIM technology can integrate a large amount of information in engineering construction on the basis of three-dimensional technology. At the same time, China's tax authorities vigorously promote the implementation of the pilot reform of the camp. Under such a background, China's construction industry is required not only to pay attention to economic development. The energy problem should also be placed at the key position in the process of enterprise development, which requires relevant units to constantly improve the level of project cost management. Under the implementation of the reform of the tax system of the business reform, the requirements of the project cost on marketization and informatization are more strict. Under the implementation of the reform of the tax system of the business reform, the requirements of the project cost on marketization and informatization are more strict. BIM Technology is fast, accurate in cost calculation and real-time control of the construction dynamic, multi angle problem and efficient cost control problem. BIM is no longer limited to plane, and the data drawn is not limited to points, lines and faces, but involves the building components with accurate parameters such as walls, doors, windows, etc. BIM Technology has the advantages of fast calculation, accuracy and stability, and can control the construction process of the project in real time. This paper mainly discusses and analyzes the project cost management based on BIM Technology under the operation reform and increase, and seeks the key points of project cost management in this process, and provides a theoretical support for the construction of various projects in China.