Landfill is the place to disposal the municipal solid waste(MSW). During the design and construction, special attention was paid to the landfill settlement which affected on the capacity, stability, and the surrounding. Based on some hypotheses, the mechanism of settlement of landfill was comprehensively studied with the analytical method in this paper and some useful conclusions were obtained. The main studies of this paper were as following:1) Some existing landfill settlement models were commented and classified. Based on geotechnical theory, the compression settlement was divided into immediate settlement、primary settlement and secondary settlement. Based on the mechanism of biodegradation, the biodegradation settlement could be obtained from the analysis of the mass loss regulation and the analysis of formulation between the mass loss and the volume loss. The relationship between the compression and biodegradation should be taken into account when calculating the landfill settlement.2) A set of systemic experiments to simulate the stabilization of landfill was carried out, which consist of some routine experiments and column settlement experiment. Routine experiments include tests of special gravity, field capacity, compression, rheology, permeability and biodegradation. The apparatus of column settlement experiment was designed to carry on laboratory settlement experiment specially, which can measure the settlement, the volume of leachate and gas. These data were very useful for theory studying.3) The biodegradation mass loss regulation should be characterized with the Richards model from the result of column settlement experiment. A new formulation of conversion between the mass loss and the volume loss was put forward from the mechanism of biodegradation and some result of laboratory experiments.4) The alter rules of the immediate modulus and primary compression index related on some familiar factor were studied and some useful conclusions were gained.5) Based on the unsaturated consolidation theory, the control equation of primary