The invention discloses a combined structure of four homodromous turning L-shaped arch bridges. The four homodromous turning L-shaped arch bridges are combined into a structure which enables direct running vehicles and large radius turning vehicles in a crossroad to run smoothly without crossing occupation. The four homodromous turning L-shaped arch bridges are combined into a hollow cross structure, four upper bridge sections are at the far end of the hollow cross structure far from the center, and four lower bridge sections are at the central area of the hollow cross structure; and the lower bridge sections of the four homodromous turning L-shaped arch bridges turn counterclockwise or clockwise. The combined structure has the advantages that: the purpose of crossing occupation-free smooth running of the direct running vehicles and the large radius turning vehicles in the crossroad can be fulfilled by matching the proper division of straight running and large radius turning lanes on the ground through the four homodromous turning L-shaped arch bridges. The combined structure realizes the technical schemes of greatly saving the engineering cost and realizing smooth running at the crossroad, and solves the problem of traffic jam due to occupation at the crossroad.