This project defines and generalizes the groundwater flow and soil deformation in geotechnical engineering by combining the hydrogeological conceptual model. Based on the fluid-solid coupling theory, a coupled model of groundwater flow and soil deformation is constructed, and the SUB program package in MODFLOW simulation software is selected to numerically simulate and analyze the relationship between groundwater flow and soil deformation in the study area. In layer2 and layer3, the trend of groundwater level decline and soil compression is shown, and the other layers4~layer9 also show the same situation, due to the over-exploitation of groundwater, resulting in serious decline of the soil in the study area, which reveals the causal relationship between groundwater flow and soil deformation at present.