Abstract: In order to understand the mechanism of land subsidence in the plain area of eastern Hebei Province and to reveal the main influencing factors that induced land subsidence, the plain area of Tangshan City was studied as the research object.By analyzing the current land subsidence in the study area, the nature of the Quaternary strata and the depth of groundwater level, the main factors causing land subsidence were systematically explained, and the land subsidence susceptibility was evaluated based on the comprehensive risk index method.The results showed that:(1) Land subsidence in the study area gradually increased from north to south, and the areas with serious settlement were located along the coast; the area of high susceptibility to land subsidence in the study area was 1 859.74 km2,accounting for 22.30%;the area of medium susceptibility was 2 699.34 km2,accounting for 32.36%;the area of low susceptibility was 3 781.92 km2,accounting for 45.34%.(2) The internal factors of land subsidence were the thickness of the Quaternary strata, the thickness of clayey soil of main groundwater extraction layer, and the external influencing factors were the burial depth of shallow and deep groundwater level.The research results can provide scientific basis for improving the monitoring and early warning capability of land subsidence disaster.