The microbial lipases are industrially more substantial. The bacterial lipase enzymes can be extracellular and intracellular, and are extremely affected by bacterial nutrition and various physicochemical factors like temperature degree, pH, the sources of carbon and nitrogen, inorganic salts and agitation. The objective of current work is isolation and identify of P.
aeruginosa from crude oil contaminated soil depending on PCR targeted lipA gene. 20g (15 samples) of crude oil contaminated soil were collected from north oil refineries/Kirkuk/Iraq. The isolates were identified according to microscopically diagnosis and colonial properties, biochemical tests, API-20E system with diagnosis by PCR technique based on gene lip A. PCR products by electrophoresis demonstrated only 8 isolates (53.33%) with positive results with lipA 558 from all isolates of P. aeruginosa.