Soil samples were collected from five sites covering petroleum exploration station in Kukawa, Kukawa Local Government Area of Borno State, Nigeria between October, 2012 and February, 2013 at two different depths (0-10cm and 10-20cm) to enumerate and identify hydrocarbon degrading fungi in the soil. Total fungi (TF) on Sabraoud dextrose agar (SDA) and hydrocarbon utilizing fungi (HUF) were enumerated on Oil agar (OA). The fungi were identified using macroscopic and microscopic examinations. It was observed that the fungi (TF, and HUF) were more densely populated at 10cm depth. (TF: 1.1×102 – 2.4×102 cfu/g, and HUF: 8.0×104 – 11.0×103 cfu/g than at 20 cm depth (TF: 5.0×102 – 13.0×102 cfu/g, HUF: 3.0×102 – 7.0×102 cfu/g). The HUF was genera of Penicillium, Aspergillus, and Rhizopus. Aspergillus species were represented by Aspergillus niger, Aspergillus umigates, and Aspergillus oryzae others were Rhizopus oryzae and Penicillium notatum. While the distribution of hydrocarbon utilizing fungi and their percentage of occurrence show that Aspergillus niger, Aspergillus oryzae, Aspergillus, umigates and Penicillium notatum occurred (100%), only Rhizopus oryzae occurred (80%). Aspergillus niger and Penicillium notatum were able to grow luxuriantly (+++) while Aspergillus umigates, Aspergillus oryzae and Rhizopus oryzae grow moderate (++). The weight loss of crude oil by Fungi ranged from 25.0% to 48.3% after 21 days. Of the fungi Penicillium notatum and Aspergillus niger were more potent in utilizing the crude oil and degraded 48.3% and 44.3% of the oil after 21 days respectively.
 

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