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This study assessed levels of potentially toxic metals and organochlorine pesticides residues (OCPs) in poultry feed obtained from three feed mills in Iwo, Osun State, Nigeria. The proximate analysis was carried out using method described by Association of Official Analytical Chemists (AOAC), potentially toxic metal with AAS and OCPs with GC-ECD. The proximate analysis mean levels are as follows: moisture {broiler feed (6.33 ± 0.8%) layer mash (9.17 ± 4.9%)}; ash {broilers (8.33 ± 2.6%) layers (9.17 ± 4.9%)}; fibre {broilers (0.33 ± 0.2%) layers (0.20 ± 0.2%)}; dry matter {broilers (93.7 ± 0.8%), layers (93.0 ± 1.7%)}. The mean values of OCPs ranged from 0.34 ng/kg to 14.8 ng/kg in broilers and 0.07 ng/kg to 1.74 ng/kg in layers mash. In broilers feed, aldrin, endosulfan I and endrin, exceeded the Maximum Residue Limits (MRL) for Animal Feed for OCPs, while in layers mash, aldrin and endrin aldehyde exceeded the MRL limits. The levels of Cu Zn and Pb in broiler and layers mash obtained in this study were far below the maximum recommended concentrations as stipulated by European Union for animal feed. These results indicated the presence of OCPs in poultry feeds which could bioaccumulate and eventually lead to the contamination of table eggs and table meats as a result of these toxic materials.  
Keywords: Toxicology, persistent organic pollutant, contamination, animal feed, monitoring.