Abstract: Landfill is a cost-effective method for urban wastedisposal. Prediction of landfill settlement is the most essential issuein order to increase the municipal solid waste landfill capacity and improvethe utilization of landfill. In this paper, a mechanical model of thesettlement under the combined action of load, creep and biodegradationis proposed based on the settlement mechanism of municipal solid wastelandfill and the relationship between stress and strain in classical mechanics.The expression of yield surface stress increment is obtained under load,creep and biodegradation. The example computed oflandfill settlement shows that the model is satisfactory in forecasting.