Ecological problems have long been a hard issue in mining cities. This paper tried to present ecological functions in mining cities from two aspects: landscape ecology and ecological carrying capacity. The city of Qitaihe, one of the coal cities in Heilongjiang Province in northeastern China, was chosen as a typical study area. Remote sensing data from 1957, 1985, 2000, and 2015, and geographic information system (GIS) techniques were employed to obtain land use and cover information. Methods of landscape pattern indexes and a modified model of ecological carrying capacity which added social and economy index were used to study the spatial and temporal variation of the ecological condition. Results showed that the landscape pattern changed tremendously during the study period due to interference from human activity. The degree of aggregation, dominance, and fragmentation of mining land showed an increasing trend. On the other hand, the ecological carrying capacity per capita declined by 37.4% from 1985 to 2000. Except for the growth of population, the dim social and economic conditions had an impact on this decline too. In addition, spatial distribution of land types and ecological carrying capacity also had some correlation with the city’s overall planning. The obtained results also provided suggestions that future research should encourage the combination between ecology and economy, as well as urban planning.