Abstract: The present invention relates to road traffic field, providing a two-level continuous flow crossroad and construction method and prefabricated parts thereof. The crossroad comprises a first road and a second road intersected with each other. At least one overpass or underpass crosses the first road and merges with the second road. The overpass or underpass each has a bypass branched from one side thereof. The bypass merges with the first road. The construction method includes constructing the two roads or starting from two existing roads. The prefabricated parts include a vaulted strip main body for overpass and vaulted strip for U-turn. Upon the crossroad of the present invention, traffics can make left turn, right turn and U-turn and go ahead without interruption. The crossroad of the present invention has simple structure and takes up less land.