BIM technology, that is, building information modeling technology, has become the development trend of architectural design, which will bring a revolutionary upgrade to the construction industry. As construction projects become more and more complex, BIM technology can well meet the construction needs of construction projects, and with the help of it, designers can also complete building structure design tasks with higher quality and efficiency. Especially for some complex construction projects, problems are most likely to occur in the stage of structural design schemes, which will bring great difficulties to the construction of subsequent construction projects, so it must be optimized and controlled. BIM technology, as a technical innovation method for building structure design optimization, can exert a strong application value. This paper takes BIM technology as the research object, and focuses on the application of BIM technology in the optimization of building structure design. Firstly, it briefly points out the application advantages of BIM technology, and then discusses the application of BIM technology in optimizing the design of building structures in combination with a new city school project.