The aim of this research was to compare the levels of organochlorine pesticides and PCBs in samples of Dicentrarchus labrax living in the Straits of Messina with samples cultivated in cages in the Mediterranean Sea. Muscles and liver tissues sampled over the months, within the same year, were analyzed. The quantitative determination of the organochlorine compounds was performed by GC-ECD and confirmed with GC-MS. The results showed that the concentrations of DDTs in muscles and livers as such of reared sea bass were in the range 0.2-1.3 microg/kg and 9.6 -48.4 microg/kg, respectively. In wild fish the concentrations of DDTs were very much lower: 0.1 microg/kg in muscles, 5.1-9.0 microg/kg in livers. Total PCBs levels were higher in cultivated sea bass than in wild fish; the concentration ranges were 5.3-59.7 microg/kg and 74.4-267.4 microg/kg in muscle and liver of reared samples, respectively, and 1.1-1.5 microg/kg and 63.2-109.4 microg/kg in muscle and liver of wild samples, respectively.