Plant rehabilitation at dump sites in alpine region is the critical issue for the sustainable development of open pit mine in China. Several artificial restoration measures were applied for plant rehabilitation in Inner Mongolia Zhahanaoer Mine. Field investigations and monitoring were continually carried out at 75 sample plots at dump site of open-pit mine of Zhahanaoer from 2021 to 2022. We analyzed plant community composition, plant cover and biodiversity. Results showed that there are significant seasonal and annual variation pattern for plant growth. The increasing plant species number with increasing restoration period may due to the coming non-planting plant species from around grassland. There are significant higher biodiversity in flat and slope topography than that of in "Tianzige". There was significant effect of slope degree on diversity, which varied with seasonal change. Plant biodiversity by spray seedling plus shrub method was significantly higher than those of other three methods. However, there were no significant differences of plant biodiversity in slope aspect, soil fertilization and irrigation treatments, respectively. Our results could contribute to the scientific evidences for plant rehabilitation of the dump sites of open pit mine in alpine region.