Little universal method is monitored p-chlorophenols compounds in environmental media. In the paper, analytic method of p-chlorophenols compound by high performance liquid chromatography (HPLC) was optimized. The result were that the mobile phase was 0.5% phosphoric acid and acetonitrile, and flow rate was 1.5mL/min. The column temperature of HPLC was 30℃, and the injection volume was 10μL, detection wavelength was 218nm. In monitoring process, the gradient elution mode determination of pentachlorophenol was used. In this condition, the pentachlorophenol, o-chlorophenol, m-chlorophenol and phenol could be seperated very well, the standard cures were Y=68.523x+360.08, Y=18.392x+17.575, Y=20.09x+16.319, and Y=26.379x+17.061, respectively. And the relative standard deviation (RSD) was 0.83%, 1.04%, 0.91%, 0.40%, respectively. The average recovery of the added index were from 89.17~100.58%.At last, sample of pentachlorophenol wastewater after biodegradation was monitored by HPLC in accordance with the optimization of the chromatographic conditions.. The result indicated that there was pentachlorophenol 12.35mg/L, p-chlorophenol 6.75mg/L, o-chlorophenol 3.24 mg/L, phenol 1.79mg /L.