[Objective] The aim was to choose appropriate floating plant in the wetland in the north China.[Method] Pistia stratiotes L.,Eichhornia crassipes,and Hydrocharis dubia（Bl.） Backer were planted in the aquatic biological pool of constructed subsurface flow wetland system in the reservoir.Through filed investigation,the growth of the three kinds of plants was studied and their adaptability to the northern climate was concluded.[Result] Judging from the growth speed and state of the three kinds of floating plants,the biological characteristic of Pistia stratiotes L.can perfectly adapt the environment in the pool in the reservoir,followed by the Eichhornia crassipes.The growth state of the Hydrocharis dubia（Bl.） Backer was the worst one and it can not adapt to the north environment.[Conclusion] It provided references for the choice of artificial floating plant in the north area.
