In order to solve the problem of submerged vegetation restoration in deep water area of Baiyangdian Lake, an ecological suspended bed constructed by aquatic plants, ropes and supporting rods was developed. The position of the ecological suspended bed can be adjusted according to the change of water level. Through monitoring of water quality around the suspended bed from July 2019 to November 2019, the purification effect of submerged plants on the suspended bed on nitrogen and phosphorus nutrients in deep water area of lake was studied. The results showed that Myriophyllum grows well on the suspended bed, and could effectively reduce the nitrogen and phosphorus nutrients in the water body. One month after the start of the experiment, the removal rates of total nitrogen, total phosphorus and nitrite nitrogen in the water around the suspended bed were 40.54%, 53.45% and 99%, respectively. At the end of the experiment, the total nitrogen, nitrite nitrogen and COD decreased by 12.43%, 33.93% and 17.09% respectively compared with those at the start of the experiment. The study shows that submerged plants on the suspended bed can effectively solve the problem of insufficient light for submerged plant growth, making it one of the effective measures to restore submerged vegetation in northern algal lakes.