Abstract: For the path analysis of network passenger flow, the effective path judgment of urban rail transit network is fundamental and critical. This article analyzes handling method of rail transit network node, and the definition and determination rules of effective and redundant sections are given. It is found in practical application that there are redundant sections in some of the effective paths that are searched. Redundant sections exist because of the special handling method of network nodes. The definition of redundant sections is given based on section features. By setting transfer node variable and judging the subsequence of path transfer node sequence, a method for identifying paths with redundant sections is proposed. Also, an improved algorithm is presented by adding redundant section judging process to existing searching algorithms. In the case study, the value of path extension coefficient is reasonably chosen and the improved algorithm is implemented by Python. The simulation result shows that the improved algorithm can correctly filter the effective paths of transit network and can output the full information of effective paths, thus validity of the algorithm is validated.