Abstract: For studying the load of the bacterium, Aeromonas hydrophila in swamps and artificial fish infection, four swamps were studied in Rajshahi University campus during November, 2001 to October, 2002. The load of A. hydrophila was found to vary from 1.16x10⁷ to 4.90x10⁷ CFU ml^-1. In the artificial infection to the snakehead, Channa punctatus, the mortality rates were recorded as 100, 75, 25, 12.5 and 0% at 3.42x10⁹, 3.42x10⁸, 3.42x10⁷, 3.42x10⁶ and 3.42x10⁵ CFU fish ml^-1, respectively. The average bacterial load in the swamps (3.42x10⁷ CFU ml^-1) was slightly higher than that prevailed in the control pond (3.13x10⁷ CFU ml^-1). Swamps can be utilized at the present bacterial load for the fish culture.