The effects of temperature, pH and incubation time on amylase, protease and cellulase activity by different species of Aspergillus in crude oil polluted soil sites in Nigeria were studied. Incubation period, Optimal pH values and temperatures for the enzymes produced by the different micro‐organisms were determined. The production of amylase by A. fumigatus and A. niger isolated from crude oil polluted sites showed that both fungi had their peaks on the first day of incubation for amylase, protease and cellulase. A. niger showed higher stability across a range of pH (3-6) and temperature (25-70oC) changes in all the enzyme activities. Further experiments are recommended to purify the secreted enzymes and stability studies will be performed to enhance the application of enzyme to commercial level.