In this thesis, we focus on the design of the fault-tolerant routing algorithm for the (n, k)-star graph. We apply the idea of collecting the limited global information used for routing on the n-star graph to the (n, k)-star graph. First, we build the probabilistic safety vector (PSV) with modified cycle patterns. Then, our routing algorithm decides the fault-free routing path with the help of PSV. In order to improve the routing performance with more faulty nodes, we dynamically assign the threshold for our routing algorithm. The performance is judged by the average length of routing paths. Compared with distance first search and safety level, we get the best performance in the simulations.