Abstract: The inhibitory performance of four indigenous plant materials, namely: pepper fruit, Dennettia tripetala Baker, clove, Eugenia aromatica Hook, black pepper, Piper guineense (Schum and Thonn) and African nut-meg, Monodora myristica (Dunal) on the main developmental stages of two main pests, namely: the leather beetle, Dermestes maculatus Degeer and the copra beetle, Necrobia rufipes Degeer on smoked African mudfish, Clarias gariepinus Burchell was investigated under laboratory conditions. The plant materials were pulverized into powders and also processed into extracts and were applied at 2.50, 5.00, 7.50 and 10.00 g per 100 g fish and 5 mL of 2.50, 5.00, 7.50 and 10.00% per 100g fish respectively. Each of the powdered smoked fish significantly (p<0.05) hindered progeny development in D. maculatus and N. rufipes. Most of the scanty eggs laid, where there was oviposition, remained unviable and the suppression rate of adult emergence was put at 99.75% and 99.60% in D. maculatus and N. rufipes infestations respectively. Similarly, each of the extract dosages significantly (p<0.05) prevented adult emergence in protected fish. The suppression rate of adult emergence in fish protected with the extracts against D. maculatus and N. rufipes was put at>99.77 and >99.55% respectively. In another study to determine the effect of each plant dosage on the palatability and aesthetic acceptance of protected smoked fish, the treated fish was organoleptically rated excellent.