Technical Abstract: With the popularity of catfish and tilapia in the healthy diet, the consumption and harvesting of farm raised finfish has increased. Since 1987 the bacterial pathogen, Listeria monocytogenes, has been isolated from seafood, particularly farm raised catfish in the United States. Seafood isolates of L. monocytogenes are now available. In order to maintain the raw finfish product, non-thermal interventions to remove bacterial pathogens need to be evaluated using these isolates. A non-thermal intervention process, irradiation, was used to determine the destruct values of the L. monocytogenes seafood isolates along with a non-pathogenic Listeria and a L. monocytogenes previously studied. The irradiation destruct values were obtained for each individual isolate inoculated on raw and frozen catfish or tilapia irradiated at 4 C or -10 C. The D-radiation values obtained for the L. monocytogenes inoculated on the raw or frozen catfish did not differ (P > 0.05) from the values obtained on the raw or frozen tilapia. The D-radiation values ranged from 0.48 to 0.85 kGy. The average D-radiation value obtained was 0.62 (SD=0.09) kGy and is typically reported of those for Listeria. The data obtained has identified a multi-isolate cocktail that can be used for future radiation inactivation studies for L. monocytogenes modeled in finfish.