A method and a system of evaluating traffic network reliability adapted to a traffic route network with sub-routes are provided. The method includes obtaining a connecting configuration, threshold distribution values, a state distribution value of each sub-route; enumerating at least one path according to a maximal threshold value of the traffic route network, the connection configuration and the threshold distribution values of each sub-route wherein each path is composed of a plurality of the sub-routes and includes threshold distribution values corresponding to each sub-route, wherein if a specific path is not composed of a specific sub-route, a threshold distribution value of the specific path corresponding to the specific sub-route is 0; and calculating a difference between user-side network reliability value and system-side network reliability of the traffic route network based on the threshold distribution values corresponding to each sub-route of each path and the state distribution value of each sub-route.
Traffic network reliability evaluating method and system thereof