Abstract: A bacterial strain, DN1, degrading p-nitrophenol (PNP) was isolated from garden soil by selective enrichment in M63 medium. Repeated subculturing in Nutrient Agar (NA) plates, NA slants and Basal Salts Medium (BSM) containing PNP (BSM+ PNP) led to isolation of pure colonies. The organism is Gram negative, aerobic, catalase positive, oxidase positive and rod shaped with mostly single arrangement. It shows bluish green pigmentation on various specialized media such as Pseudomonas P medium, Pseudomonas F medium, Modified F medium, Pseudomonas Isolation Agar (PIA) and HiFluoro Pseudomonas Agar. DN1 gave positive results with motility, citrate utilization, urease, Nitrate Reduction (NR) and gelatin liquefaction tests but negative results with Methyl Red (MR),Voges Proskauer (VP) and indole tests. It was casein hydrolysis and lipase positive but starch hydrolysis negative. Acid production from carbohydrates tested (glucose and lactose) was negative. It can grow at 42°C but not at 4°C and tolerates <5% NaCl concentration. Optimum pH for PNP degradation was found to be 7.0. Among several media tested such as M9, M63 and BSM, BSM was found to be the optimum medium for biodegradation of PNP. DN1 could degrade upto 100 mg L-1 PNP using the xenobiotic as sole carbon or carbon and nitrogen sources. On the basis of gross morphological, micromorphological, physiological and biochemical tests DN1 was definitively identified as Pseudomonas aeruginosa strain DN1. To our knowledge this is the first report of a Pseudomonas aeruginosa strain able to degrade p-nitrophenol (PNP).