In the research of this topic, combining with the existing research results and practical experience, the development direction of green roof design under the background of today's era is discussed. The new concept of green roof design of rainwater drainage and storage building guided by sponge city theory is put forward. Guided by the new concept of architectural design, the green roof design of the drainage and storage building in Shaanxi Province is empirically studied. It has important practical significance to improve the design level of the drainage and storage building. Guided by the sponge city of Shaanxi Province, it provides suggestions and references for similar design schemes in the western region.