Landfill disposal is an important part of the final disposal of hazardous wastes at present. Based on the new requirements proposed in Standard for Pollution Control in Hazardous Waste Landfill (GB 18598-2019), there are the great differences in the size selection, load value and structural calculation of landfill units in different rigid landfills. Taking a project in Yancheng as an example, the actual stress on the side wall of the landfill unit is analyzed by synthesizing the field experiment results to establish a load analysis model. The simplified structural model of the rigid landfill is established by using the structural analysis software of Autodesk Robot Structural Analysis Professional to analyze the bending moment distribution of each component under the different working conditions. The working condition combination and points for attention during the calculation are put forward. Finally, the relationship between the plane size and the cost per cubic meter of storage capacity is built according to the cell area and volume requirements of the rigid landfill, and the economically optimal cell plane size is proposed.