Mongolia is an important part of the Mongolian Plateau. Its land cover patterns and changes are of great significance for resources, environment, ecology, and sustainable development of Northeast Asia. In order to address issues such as lack of high accuracy and up-to-date land cover products in this region, we have used images obtained through Landsat thematic mapper remote sensing based on object-oriented classification method, to produce remote sensing data products and analyze the Mongolian land cover. A classification system suitable for Mongolian land cover was first studied taking characteristics of the Mongolian landscape into consideration. Interpretation algorithms and rules of 10 kinds of natural and artificial features were studied using the object-oriented remote sensing interpolation method, and a complete remote sensing interpolation technological program suitable for Mongolian land cover was developed. Land cover products for Mongolia for 2010 were obtained using one-by-one interpretation. The accuracies of the first and second-class classification of the datasets were 82.26% and 68.55%, respectively. The main land cover types in Mongolia consist of barren lands, grasslands, and forests. Out of these, barren lands account for the maximum area (approximately 47.03% of the total area) with concentrated and continuous characteristics, and are mainly distributed in the south and west of Mongolia. The second largest areas are covered by grasslands (42.64% of the total area) with clear regional characteristics, and mainly distributed in the north of Mongolia and near the rivers. Forest areas constitute the smallest part, accounting for only 8.17% of the total area, and are mainly distributed in the mountains of north and northwest Mongolia. The spatial distribution of the land cover presents clear regional differences and land type transitivity. The land cover changes from barren to desert steppe, to real steppe, and finally, to forests as one moves from the south to north. The desert steppe forms a clear separate belt in the central part of Mongolia.