Triazophos is a Thiophosphoric and is the active ingradient of the insecticide Hostathion. The aim of the study is to determine the effects of triazophos at five different concentrations on soil bacterial and fungal count. The effect of triazophos on bacterial and fungal population by incubation in soil for 7 days was determined. Results revealed that triazophos caused significant reduction in the bacterial and fungal populations. By statistical analysis, the concentrations of the pesticides as well as the dilution of soil sample were analyzed by two way ANOVA. Study reveals that both bacterial and fungal population the concentration of triazophos vs sample dilution has been significantly affected. The change in concentration brought significant reduction in bacterial count. We conclude that triazophos insecticide is using in paddy soils highly toxic pollutant to the bacterial and fungal organisms.