Abstract: Based on testing and checking by ¹³⁷Cs method and ²¹⁰Pb method, this paper quantitatively analyses 663 core samples from 13 drill holes to study the deposition rate changes in the main coastal estuaries in Liaoning Province over a hundred years. The result shows that the deposition rates vary in different areas and times. The deposition rate of estuary of Liaohe River is the largest (23.66 mm/a), belonging to medium-high rate deposition. The slowest rate is in the western Liaoning coastline, with gradually reducing trend. The deposition rate in the western Liaoning coast increases with depth. In Liaohe River of the Liaodong Bay and the estuary of Daling River, the deposition rate shows multi-peak. While in the Liaodong Peninsula on the northwestern shore of the Yellow Sea, the deposition rate reduces with depth.