Abstract: This article discusses the concept of road reliability and its application in the evaluation of road networks. A model of reliability evaluation method for urban road network based on GIS spatial analysis is established. The model described in detail geometric network connectivity methods and implementation details of the code building process based on ArcEngine components such as space search, space intersect. Using the Guangzhou - Foshan road network as an example, we analyzed the reliability of the regional road network by the equal-area grid method