Cast-in-place drainage box culvert construction formwork system

The utility model discloses a cast-in-place drainage box culvert construction formwork system which comprises an outer formwork of a Larsen steel sheet pile, and a box culvert foundation is poured at the bottom in the outer formwork. An inner mold is arranged on the upper surface of the box culvert foundation and connected to the upper surface of the steel mold trolley. The steel mould trolley comprises a trolley support, and the bottom of the trolley support is connected with a walking motor which is connected with a driving wheel. The top of the trolley support is rotationally connected with multiple adjusting lead screws, and the top ends of the adjusting lead screws are in threaded connection with the bracket. First telescopic rods are connected to the two sides of the top face of the bracket, side plates are connected to the other ends of the first telescopic rods, the bracket and the side plates jointly form an inverted U-shaped plate structure, and the inner mold covers the outer surface of the bracket