The invention discloses a highway bridge deck water drainage facility. The highway bridge deck water drainage facility comprises a mounting seat; a placing groove is formed in the top of the mountingseat; two misplaced filtering nets sticking to each other are placed in the placing groove; fixing blocks are both fixedly mounted at the bottoms of the two filtering nets; first clamping grooves areformed in the bottoms of the fixing blocks; two first clamping grooves are formed in the internal wall of the bottom of the placing groove; rotating grooves are formed in the internal walls of the bottoms of the first clamping grooves; and the same rotating columns are rotationally mounted in the rotating grooves and the first clamping grooves. When a drainage pipeline is clogged and the filteringnets are inconvenient for working personnel to clean, the vertical distance between the two filtering nets is increased by using an adjusting handle so that the blocked filtering nets generate a water drainage space; and therefore, accumulated water on the deck can be rapidly drained; and meanwhile, by lifting the filtering nets, the filtering nets can be rapidly and conveniently lifted from themounting seat so that the cleaning of the filtering nets is made convenient.