Abstract: Community composition, organization laws, above ground phytomass and habitat characteristics of three main meadow communities in the Xilin river flood land of Innermongolia were studied.The community, dominated by Eleocharis intersita, Carex enervis, Agrostis gigantea and mesic forbs, had a high aerial phytomass of 445.64 gDM·m-2, which was 2—4 times higher than the steppe phytomass. The aerial phytomass of Saussurea acuminata mesic forbs meadow and Iris lactea mesic forbs meadow were 3584.50gFM·m-2 and 1444.02 gFM·m-2 respectively. Meadow community had no obvious single edificator species, i. e. the edifocator had the smaller dominance in meadow than in steppe.DCA ordination of the 44 quadrats of the marsh, meadow and steppe communities shows: in the meadow habitats, the mesic forbs meadow occupied the relatively dry sites, the grasses meadow distributed on the moderate humid sites and the Cyperaceae meadow developed on the wet sites. The sites drier than that of mesic forbs meadow were occupied by meadow steppe ,while the sites wetter than that of Cyperaceae meadow are for marsh.