The inquiry service of public traffic routes is the important part of urban information service, which core is the public traffic route selection algorithm. However the traditional public traffic route selection algorithms have high time complexities and cannot support the inquiry of multiple changes. In this article, we put forward the speedy algorithm of public traffic route selection based on adaptive backbone network. In this algorithm, if the public traffic routes which pass certain public traffic station exceed or equal a certain value, so the station is defined as the backbone station, and the backbone stations and the public routes which pass them compose backbones network. If changes are limited at the backbone stations, so we can realize multiple changes inquiry and reduce computation in 10% of traditional algorithms through changing the certain value to adjust the backbone network.