Drainage device with filtering mechanism

The drainage device with the filtering mechanism comprises a filtering frame arranged on the surface of the ground, a water inlet pipe and a water outlet pipe are arranged at the positions, located at the upper end and the lower end of the filtering frame, of the ground respectively, a plurality of sets of inserting pipes are fixedly arranged at the upper end of the filtering frame in a penetrating mode, and the bottoms of the inserting pipes are connected to the water outlet pipe. A filter hopper is detachably and fixedly connected to the upper end of the inserting pipe, a slag discharging pipe is transversely arranged at the bottom of the side, away from the water inlet pipe, of the filter frame in a penetrating mode, a cleaning plate is further slidably arranged at the bottom of the filter frame in an attached mode, and the cleaning plate and the inserting pipe are arranged in a staggered mode. The filter frame is additionally arranged between the water inlet pipe and the water outlet pipe, large-particle