Abstract: With the continuous expansion of urban rail transit network, the network structure becoms more and more complex, the passenger travel rout between station O and station D is more diverse. Because the linkage between lines is not perfect, some situations occur frequently, for instance, passengers can not arrive the destination or wait for a long time at station. In this article, on the basis of factors affecting network accessibility, two types of algorithms were studied and the framework of the network accessibility system was designed and implemented. Meanwhile, the feasibility of the algorithms was proved, the application of network accessibility was discussed, which could play very important role in improving the efficiency, the convenience and accuracy of the passenger travel.