Spatial and temporal land-use patterns in the Songhua River Basin (SRB) over the past 20 years were analyzed; the influence of natural geographic, socioeconomic, and anthropogenic factors was considered. Using spatial analysis and geodetector modeling, we assessed various indicators to comprehensively analyze land-use changes in the SRB in a long time series (2001 to 2021). Our goal was to determine the extent to which each factor influences land-use change and the mechanisms of interaction. We found that natural geographic factors and anthropogenic factors, particularly elevation and population density, had a greater influence on land-use changes than climatic and socio-economic factors. Despite a positive trend in land use indicated by the composite index, the SRB is experiencing a decrease in undeveloped land resources annually. We also identified that interactions between factors had varying effects, with the superposition of multiple factors potentially exacerbating conflicts between different land-use types. These findings provide valuable insights for strategic planning, policy formulation, and optimization of land resources in the Songhua River Basin.