Shaped water filtering and draining system for retaining wall and construction method

The shaped water filtering and draining system comprises a plurality of water filtering and draining parts and a plurality of water filtering and draining blind pipes which are arranged in a backfill soil layer behind the retaining wall, the water filtering and draining parts are fixedly connected with water draining holes of the retaining wall, and the water filtering and draining blind pipes are arranged between the adjacent water filtering and draining parts. The plurality of water filtering and draining pieces are connected with the plurality of water filtering and draining blind pipes to drain water from a backfill soil layer behind the retaining wall; according to the retaining wall shaping, filtering and drainage system, the problems that a traditional water filtering facility is prone to displacement, a water filtering device fails, and retaining wall drainage holes are prone to being blocked are effectively solved; meanwhile, the problems that water on the wall back seeps from the wall body and the w