A study was conducted to evaluate the potentials of Pseudomonas aeruginosa and Penicillium janthinellum and their mutants in degradation of crude oil in river Kaduna effluents after two weeks incubation at 30°C, Degradation potentials ranged from partial to good. A mixture of the pure strains and mutants (subjected to 10-minute irradiation) of the two micro-organisms, as well as the pure strains of Pseudomonas aeruginosa showed the best degradation. Five and fifteen minute mutants of the two micro- organisms, as well as the pure strains of Penicillium janthinellum showed partial degradation. Against pristine and phytane as biomarkers, Carbon 23 (C 23 ) did not appear in the chromatogram of effluents that had undergone partial or good degradation.All consortia were observed to have significant decreases in contents of phenol, oil and grease, phosphates, ammonia, nitrates, and sulphates after two weeks of incubation at 30°C. A comparative analysis of the effluent after two weeks of incubation in relation to FEPA specifications and KRPC treated waste water (TWW) after bioremediation, revealed that, in River Kaduna water sample the phosphate concentration of most consortia were greater than TWW, and FEPA limits, except for consortia G 1 and H 1 that were lower. Other physicochemical parameters showed a lower concentration compared to that of TWW. At the end of experiment, all the consortia except G 1 and H 1