Filter material backfilling device for dewatering well construction

The utility model relates to a filter material backfilling device for precipitation well construction, which comprises a funnel and a blocking piece, and the straight pipe section of the funnel can beinserted into a filter material filling gap between the inner wall of a precipitation well and the outer wall of a filter pipe so as to realize the feeding of the funnel to the filter material filling gap; the blocking piece comprises a column core, the column core can be fixed to an upper end opening of the filter pipe to complete blocking of the upper end opening of the filter pipe, and the upper portion of the column core is of a conical structure. A supporting piece is fixedly and annularly sleeved with the middle of the column core, the cross section of the supporting piece is annular, the outer diameter of the lower end face of the supporting piece is larger than the inner diameter of the filter pipe, the outer diameter of the column core is smaller than the inner diameter of the filter pipe, and the lower