The bacterium Edwardsiella ictaluri is one of the most significant pathogens of farmed catfish in the United States of America, and has also caused mortalities in farmed and wild fish in many other parts of the world. Wild fish populations in Australia are considered free of this and many other diseases that impact fish elsewhere; although the bacterium has previously been detected in imported ornamental fish and native catfish held in Australian aquarium facilities, which may present a vector for invasion. A risk-based sampling model was constructed and wild catfish from 15 sites across the continental expanse of northern Australia were tested for E. ictaluri. The bacterium was isolated in eight Wet Tropics tandan (Tandanus tropicanus) from the Tully River, Queensland, and results were confirmed using conventional biochemical tests, and DNA sequencing. This is the first report of Edwardsiella ictaluri in wild fish on the Australian continent.