The native environment in northwestern China is characterized by a loose surface, gullies, a dry climate and serious soil erosion. The purpose of this study was to reveal the effects of the subsidence of a coal mine on plant diversity and community structure. For this purpose, six sample plots were surveyed at the Daliuta coal mine based on different subsidence times. The species richness and importance value as well as α diversity indexes were applied. The results indicate that species richness varied across study sites. Coal mine subsidence had little effect on plant diversity and community structure. The number of species increased in subsided sites in loam soils, especially in the number of unique perennial herbs, but there were no differences in sandy soils. There was less biomass in the subsidence sites than in the control sites after several years of subsidence. The community structure did not change in general, but on some loam soils constructive species changed in response to coal mine subsidence. Surface subsidence induced by coal mining can be characterized as an intermediate disturbance to plant communities in northwestern China.