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As a part of the “two screens and three belts”, the northeast forest belt is a typical forest ecosystem in China. Studying its landscape pattern and changes is of great significance for assessing the ecological security of Northeast China. Based on the MODIS remote sensing images of 2000, 2005, 2010 and 2015, the landscape types of the northeast forest belt were divided into six categories: forest, grassland, wetland, farmland, artificial surface and other land use. The changes of landscape pattern in the northeast forest belt from 2000 to 2015 were analyzed in terms of ecosystem structure, direction of ecosystem transformation and landscape index. MCE-CA-Markov model was used to simulate the changing trend of landscape pattern in the northeast forest belt in 2020. The results showed that during the past 15 years, the ecosystem as a whole was in a stable state. The trend of ecosystem improvement in the first ten years was better, but the trend of change in the next five years was slower. The artificial surface was increased year by year, and the urbanization process was accelerated. The fragmentation of grassland was intensified in 15 years, while the degree of fragmentation of forests iwa low, and the changes in 15 years were small. It was feasible to use MCE-CA-Markov to simulate the evolution of landscape pattern. The results of the landscape pattern of the northeast forest belt in 2015 were consistent with the MODIS classification results. The Kappa coefficient was 0.9181 and the relative accuracy was 80.88%. The forecast results of the northeast forest belt in 2020 showed that the proportion of forests and farmland would further decline, and the proportion of grassland and artificial surface would further increase. The forecast results indicated that the ecological environment restoration and reconstruction in the northeast forest belt would face great pressure.