Abstract: A nonlinearly effective function of biotic and abiotic factors, 1-a(c/c₀）^θ, was constructed. The modified model, which contains exponential decrease, the linear and nonlinear effects in pocess of degradation through adjusting the parameters by itself, is a self-adaptive model of nonlinear kinetics for degradation of pesticides. The modified model can describe the case in which the degradation curve descends in two forms of concave and convex with inflection point and can be applied to calculate the accumulative residualand the limit of pesticides used continually within the same time interval that, is applicable to a good many cases. The model shows higher fitness and accuracy than other models in the examples of practical applcation.