Abstract: The paper chromatography with fluorescence spectrophotometric method based on the national standard "living drinking water determine method" GB5750-85 was used to measure benzo(a)pyrene(Bap) in living drinking water.The precision of this method was bad,so high performance liquid chromatography(HPLC) was employed to measure Bap.The experimental results indicated that it was not only a rapid and accurate method,but also an excellent repeatability.The linear ranges and correlation coefficient of this method were 4.0-30.0 ng/L and 0.9999,respectively.The average precisions in one day and between days were less than 4.0%(n=5),and Bap recoveries were 89.0%-93.4%.Bap was decomposed easily when it met the light,so it should be analyzed as soon as possible after sampling.