Representative samples of channel catfish (Ictalurus punctatus Rafinesque) were obtained from five processing plants and analyzed by gas–liquid chromatography for fatty acid composition of muscle tissues. Twenty-three fatty acids were measured. The saturated fatty acids comprised 26.5%, monoenes 48.1%, dienes 13.0%, trienes 3.1%, tetraenes 3.6%, pentaenes 1.3%, and hexaenes 1.9% of total fatty acids. Fatty acid composition varied significantly (P <.01) among fish obtained from the same plant, and in addition, significant variation associated with processing plant was observed for some fatty acids.