The leaf switch failure would seriously affect the use of high performance computer system with K-Ary N-Bridge topology. In order to improve the usability and maintainability of that topology, a routing fault-tolerant strategy based on misrouting algorithm was proposed. The basic idea was to bypass the failed leaf switch leveraging misrouting, jump to other leaf switches in the same dimension, and then reached the destination node through the normal route. The proposed fault-tolerant strategy could shield the failed leaf switch without affecting the system usage. A fault-tolerant experiment was carried out in a practical K-Ary N-Bridge topology. The result shows that this fault-tolerant strategy can quickly shield the failed leaf switch as expected and can effectively improve the efficiency of system maintenance.