A kinetic model for the solid state fermentation of swine manures under both aerobic and anaerobic conditions have been proposed. The rate of CO2 production is used as an indicator of the degree of stabilization of swine manures. Analysis of available experimental data suggests that the initial rate of stabilization, as measured by the product of the reaction constant and the initial activity of bacteria, increases with temperature and correlates with the initial moisture content of swine manures. The rate of deactivation of bacteria, as reflected by the deactivation rate constant, is relatively constant for low and medium temperatures (25-35 degrees C) and is fast for higher temperature (45 degrees C). The optimum operating scheme should adopt a medium high temperature (35 degrees C) and an appropriate amount of initial moisture.