[Objective] The boundary characteristics of the Inner Mongolia reach of the Yellow River were studied in order to provide an important theoretical basis for the construction of embankment protection in the reach.[Methods] The river boundary information of the Inner Mongolia reach of the Yellow River for the past 30 years was extracted based on the modified normalized difference water index(MNDWI) and seven phases of the Landsat satellite images taken from 1988—2018. After calculating the swing area, the maximum swing area, the swing direction, and the other indicators of the river in different periods, the spatial-temporal variations of the river were analyzed.[Results] The upper sections of the Inner Mongolia reach of the Yellow River in the Bayangaole-Sanhuhekou and the Sanhuhekou-Baotou bend(both with greater curvatures than other locations) section oscillated more seriously than the other sections, and the whole reach showed a trend of migration to the right bank. The spatial and temporal differences in the channel swing were influenced by the material composition of the riverbed, hydrodynamic conditions, water conservancy projects, soil and water conservation projects, and other human activities.[Conclusion] Embankment protection construction in the Inner Mongolia reach of the Yellow River should focus on sections of Bayangaole-Sanhuhekou, and the Sanhuhekou-Baotou bend, with their large curvature.