Abstract: A method of GC for the determination of polychloro-biphenyls in various tissues (muscle, viscera and whole cowry) of abalone was proposed. The samples were extracted ultrasonically with n-hexane and purified by sulfuric acid. Sample of muscle tissue was purified further by florisil solid phase extraction (SPE) column, while the samples of viscera tissue and whole cowry were purified further by both florisil SPE column and Carbon-GCB SPE column. The eluate was separated on DB-5MS capillary column and detected by ECD. Linear relationships between values of peak area and mass concentration of the 7 polychloro-biphenyls were kept in the same range of 1.25-100 μg·L-1 with detection limits (3S/N) in the range of 0.04-0.06 μg·kg-1. Tests for recovery were made at the concentration levels of 0.25, 2.50 and 20.0 μg·kg-1·L-1 of mixed standard, giving values of recovery and RSD′s (n=5) in the ranges of 78.0%-102% and 3.4%-6.9% respectively.