A bacterial strain ADZ1 that demonstrated higher efficient in the aerobic denitrification was isolated from the sewage of urban rivers on the selective medium, Bromothymol Blue (BTB), after enriched in the shaking flasks. The reduction efficiency for nitrate and the total nitrogen reached 93.1% and 34.7% within 48 hours respectively. Sequence of 16S rRNA suggested that strain ADZ1 belongs to the genus of Pseudamonas, and further was identified as Pseudomonas putida by VITE K? 2 systems. With the growth conditions that the ethanol served as the carbon source and C/N ratio was 12:1, the efficiency for nitrate and the total nitrogen reduction reached 98% and 41.3% respectively. Due to the broad adaptability to dissolved oxygen and pH, together with the high activity for aerobic denitrification, this strain showed the potential application in the future.