The invention relates to a tramway transport system powered by a power line. The tramway transport system powered by the power line is characterized in that friction electrification contact wires are connected in a section way and are paved on road surfaces of lanes; the friction electrification contact wires are mutually isolated in an insulating way; the length of each section of friction electrification contact wire is smaller than the length of a shortest tramway chassis; the friction electrification contact wires communicate with the power line through a contactor respectively; only when a tramway passes through the upper part of each section of friction electrification contact wire, an electromagnet of the contactor can be drawn through a trigger mechanism arranged on the tramway, and the corresponding friction electrification contact wire is powered on; after the tramway passes, the electromagnet of the contactor is separated, and the corresponding friction electrification contact wire is powered off; a pantograph is arranged under the tramway chassis, and is continuously electrified through friction between the pantograph and each section of friction electrification contact wire, so that the tramway is driven to run.