Abstract: Based on two kinds of experimental regression and fitting relationship between coefficient of permeability and void ratio as well as the relationship between effective stress and void ratio of soil, an expression between coefficient of consolidation and effective stress is derived.A series of calculation examples and laboratory test are conducted to study the variety law of coefficient of consolidation of soft soil with different consolidation stress under compression, and proposes the cubic polynomial regression and fitting equation on coefficient of consolidation of soft soil considering effective stress.The obtained results verified that when the variety in coefficient of consolidation of soft soil under an increase of effective stress is considered, consolidation rate of soft soil foundation is usually faster (C_c/C_k<1) , or slower (C_c/C_k>1) than traditional Terzaghi consolidation theoretical calculation of it.The proposed result reduces to Terzaghi's theory for a special case of C_c/C_k=1.An unified cubic polynomial fitting relationship between coefficient of consolidation and effective stress is adopted in a very good fitting effect.The positive results can increase the accuracy for the numerical analysis of consolidation, and deformation rate of soft soil foundation can be predicted accurately.