Abstract:The counting of Pseudomonas aeruginosa（P.aeruginosa）in excess of the standard has become a common barreled drinking water failure indicator.To understand the pollution，Pseudomonas aeruginosa was detected in 82 baches barreled water by conventional microbiological test method.The ribotyping fingerprint of the isolates were analyzed.Pseudomonas aeruginosa was detected in 18 samples，and the detection ratio was 22.0%.Typing analysis of 36 isolates were done by ribotyping and matrix-assisted laser desorption/ ionization time of flight mass spectrometry（MALDI-TOF MS），and then the results were compared.The isolates were divided into two groups，including 16 and 20 isolates，but the isolates in each group were different.According to the results of typing analysis，contamination analysis could be performed and the database could be established.This will provide data support for the traceability of Pseudomonas aeruginosa in barreled water.