A method and system for aiding the taxiing of an aircraft on an airport domain enables automatic planning and execution of taxiing. The system includes a trajectory generating device for generating a taxiing trajectory of the aircraft on the airport domain, with the aid of a navigation data base, and piloting aiding devices that use the trajectory for aiding the taxiing of the aircraft. For example, the piloting aiding devices may include an automatic piloting/taxiing device and a display device.