Studies on toxic effect of Furadan (a carbamate pesticide) on histopathology of gill edible air breathing fish, Channa punctatus have been made. The LC values of furadan were calculated to be 1.25, 1.12.0.99 and 0.91 ppm 50 respectively for 24h, 48h, 72h and 96h and its regression equatior for 24h, 48h, 72h and 96h are y = -4.50 + 49.2 X ; y = 4.54 + 44 X ; y = 1.26 + 34 X and y = -6.9 + 28 X respectively. The dose or the test concentration for chronic exposure of furadan was determined by adopting the formula of Hhart et al. (1945) which explain as C = 48 hours LC X A/S2 and 50 S=24 hours LC values/48 hours LC the safe concentration suggested in the present study may help to minimize 50 50 water pollution by both the pesticides.