The invention relates to a prawn culture technique, in particular to a closed circulating seawater prawn pond culture system, which sequentially comprises a square or round culture pond, a round or square, corner-rounded vertical flow sedimentation pond, a comprehensive shellfish and algae treatment pond and a constructed mangrove wetland; the area of a single culture pond is 0.4 to 0.6 square meters, the culture pond consists of 2 to 3 prawn ponds, the pond depth is 2 to 2.2 meters, and the water depth is 1.6 to 1.8 meters; a circumferential inner wall (2) of the vertical flow sedimentation pond is inclined upwardly, the upper edge of the vertical flow sedimentation pond is provided with an annular water outlet channel (1) and a water outlet pipe (8), a mud-collecting pit (5) is arranged at the center of the bottom of the vertical flow sedimentation pond, and is connected to the outside of the pond through a mud discharge pipe (4), a central pipe (3) is arranged over the mud-collecting pit (5), and is supported and fixed by a support (6) at the center of the bottom of the vertical flow sedimentation pond, the lower part of the central pipe (3) is provided with a reflective plate (7), and a water inlet pipe (10) connected into the pond is extended into the lower part of the central pipe (3); the vertical flow sedimentation pond is 2.5 to 3 meters deep, and the water depth is 2 to 2.5 meters; the water depth of the comprehensive shellfish and algae treatment pond is 1.6 to 1.8 meters, and filter-feeding shellfish and algae are cultured in the pond by way of hanging; and the hydraulic power of the constructed mangrove wetland stays for 12 to 24 hours. In the culture system has the advantages that the polluting substances produced in the process of prawn culture can be fully and effectively removed, the structure is simple, the removing efficiency is high, the occupied floor area is small, energy can be saved, and emission can be reduced.