The invention discloses a suction anchor capable of automatically removing soil plugs. The suction anchor capable of automatically removing soil plugs comprises an anchor barrel with the open lower portion. A drainage hole communicating with the interior of the anchor barrel is formed in the top of the anchor barrel. A rotary sprayer communicating with the outside is installed on the center portion of the top inside the anchor barrel through a bearing. The inner ring of the bearing and a top cover of the anchor barrel are connected into a whole. The bearing is hollow, so that a channel for the rotary sprayer is formed, and the channel is connected with the outside. The upper half part of the rotary sprayer is a short hollow tube with the same diameter as the outer ring of the bearing, and the upper end of the short hollow tube and the outer ring of the bearing are fixedly connected into a whole. The lower half part of the rotary sprayer is a semicircular disc with the hollow inside, and the planar fracture surface position of the semicircular disc is in sealed connection with the lower end face of the hollow short tube. The cavity of the short hollow tube communicates with the cavity of the semicircular disc. Water guiding tubes are arranged at the arc edge of the semicircular disc, and the included angles between the water guiding tubes and the fracture surface of the semicircular disc are 0 degree, 30 degrees, 45 degrees, 60 degrees and 90 degrees correspondingly. The water guiding pipes communicate with the cavity of the semicircular disc. The suction anchor is simple in structure, convenient to use and capable of removing soil plugs.