Determination of the level of organochorined pesticides and polychlorinated biphenyls in seawater， organisms and sediment in Bohai Bay showed that the concentrations of total BHC, total DDT and PCBs. were in the range of 55.25-328.25 ng/L, 1.28-6.17 ng/L and 3.50--6.70 ng/L in seawater; 5.58-36.24 ng/g， 0.27-3.15 ng/g and 2.17-8.80 ng/g in sediments; and 14.43-69.51 ng/g, 1.80-3.70 ng/g and 4.30-8.80 ng/g in organisms, Arca subcrenata Lischke, respectively. . Investigation of the distribution features of DDT, BHC and PCBs in seawater, sediments. and organisms in Bohai Bay showed that pollution of DDT, BHC and PCBs. were not serious.