Abstract: For establishing the system of quantitative analysis for soil bacteria population,3 soil treatments including the sample P1 and P2 which was polluted by polycyclic aromatic hydrocarbon(PAH),and sample C from bare land were sampled and analyzed.Using the molecular cloning method,the standard substance of real-time PCR was structured,and the relevant parameter was optimized including the linearity(R²),amplification efficiency(E) and slope(S)of the standard curve.The results indicated that the relevant parameter is regular for real-time PCR,which R² was 0.985,E was 101.7% and S was 3.282.The quantity of bacteria cell in soil sample P1,P2 and C was quantitated as 1.4×10⁹,4.0×10⁹and 5.0×10⁹ respectively.It indicated that the abundance of soil bacteria could be quantitated by the established system of real-time PCR using unknown sensitive template.