Studied in this paper is the reconstruction scheme of the Tianchi Mountain Interchange Project of Suzhou Belt Expressway. The problems existing in current Jianchi Mountain Interchange are analyzed herein and five reconstruction principles are proposed. On this basis, four transformation schemes are put forward, which are "leaf type double-layer interchange + straight level crossing ", "Y-type three-story interchange + straight up span", "B-type single trumpet interchange + straight level crossing" and " optimized B-type single trumpet interchange + straight level crossing". The comprehensive comparison and selection are made from the aspects of interchange capacity, driving safety, interchange floor space and aesthetics of interchange alignment. Finally, the optimal design method is selected. The implementation of the reconstruction project brings about the following good effects: It meets the steering function of the interchange, makes the best use of the original interchange facilities, saves resources, ensures traffic safety and meets the carrying capacity. It has become the first gateway of the high-tech zone for entering and leaving the belt expressway, promoting the integrated development of highway and urban expressway.