Through experiments,this paper verifies a rate model for microbial degradation of pesticides:-dx/dt=kxm,where x is the concentration of pesticide at time t,k the rate constant,and n the number of pesticide-degrading microorganisms at time t.For microbial degradation of r-BHC in a submerged soil,there was a strong positive correlation between -dx/dt and xm (the product of x and m)where x is the concentration of r-BHC,and m thr bacterial coupe.According to a nonlinear relation between m and m=ζ₁+ζ₂x+ζ₃x²(ζ₁,ζ₂ and ζ₃ are constants),there was a significarnr correlation between the bacterial count and the concentration of r-BHC.This paper further discusses kinetic models describing the effect of pesticide concentration and temperature on the loss rate of pesticides in soil.