Pseudomonas aeruginosa is a pathogen bacterium that may cause infection and is commonly found in fish, plants, animals, soil, and water. The abundance of fish and seafood contributes to the seafood sector's economic importance. Several nations rely on the abundance of fish and seafood to support their economies. The objective of this study is to isolate P. aeruginosa and investigate its phylogenic similarity and sequencing to that of referred isolates taken from fresh fish (Cyprinus carpio) and marine (Hammour). One hundred and twenty raw fish samples were gathered from the local marketplaces in Al-Diwaniya City. The isolates of pseudomonas aeruginosa were grown on selective agar, such as chrome-genic pseudomonas agar and cetrimide agar, then identified using microbiology. and biochemical testing. According to the findings the result of PCR detection 16SrRNA gene (21.6%), Las B (5.4%),Oprl gene (4.6%). Furthermore, a phylogenic tree was established to identify the genetic proximity of different species of the eight isolate gene sequencings, the following GenBank accession numbers were determined and submitted: PP534998, PP534999, PP535000, PP53501, PP535002, PP535003, PP535004, and PP535006. The results showed that the isolation rate of P. aeruginosa in local carp was (28%) higher than the rate of isolates from marine fish (9%) when employing PCR. P. aeruginosa isolates exhibited high similarity (96%) for strains isolated from the United States, followed by (88%) for strains isolated from Iraq, and a lower similarity percentage (55%) with other strains recovered from the United States. In conclusion, the PCR is a reliable tool for molecularly detecting Pseudomonas aeruginosa that infected both local carp.