An investigation was conducted on fungal disease of freshwater fishes in Natore district of Bangladesh from September 2005 to February 2006. A total of 2097 fish specimens where about 300 fishes under 15 fish species (8 culturable and 7 non culturable) were infected with fungal disease. Among culturable species most fungal infected fishes was C. mrigala (24.71%) where the total length, total weight and group of this infected fish was 10.8 to 40 cm, 10 to 995 g and 10.1 to 15 cm respectively followed by C. idellus (16.28%) and L. rohita (13.43%). Among non culturable species the most fungal infected fish was C. punctatus (22.42%) where the total length, total weight and group of this infected fish was 11 to 23 cm, 15 to 20 g and 20.1 to 25 cm respectively followed by C. striatus (16.88%) and P. ticto (15.31%). Disease in culturable fish species was less (13.40%) than non-culturable species (15.19%). Three genera of fungi were identified where Branchiomyces sp. was associated with gill rot disease and Saprolegnia sp. and Aphanomyces sp. were associated with ulcer types of disease. The incidence (%) of disease was highest in the month of December (22.49%) followed by November (20.25%) and January (18.00%).