The zonal distribution of vegetation in Hulunbuir steppe is meadow steppe and typical steppe from east to west. And there are five different grassland types in Hulunbuir in order: Chrysanthemum tenuifolia, Stipa bayal, Leymus chinensis, Stipa grandis, and Stipa krylosti. These five grassland types constitute different grassland types and combinations in Hulun Buir, and are the main body of the grassland in Hulun Buir. Through the field study on the changes of plant community in a long-term fixed plot of Leymus chinensis meadow steppe in Outer Hulun Buir, this dataset contains plant community characteristics, including plant community coverage, plant community height, plant community abundance, and aboveground green stock of the plant community were collected and arranged from 2009 to 2015. We studied changes in the plant community in the long-term fixed sample plot of Leymus chinensis meadow grassland in Hulunbuir. Researchers can retrieve data on the characteristics of the plant community by survey year. The establishment and sharing of long-term monitoring data sets of plant communities in Leymus chinensis meadow steppe in Hulunbuir is important for continued research. The data can support ecological monitoring of warm meadow grassland and dynamic research into plant community characteristics of this steppe type in the context of global climate change and human disturbance. This study provides a theoretical basis for understanding the response law of the grassland ecosystem and the restoration and succession of the grassland ecosystem under long-term enclosure.