The influence of three levels of nitrogen on the incidence of sheath rot disease of paddy caused bySarocladium attenuatum was studied under field conditions using one resistant (Bhavani) and one susceptible (Kannaki) variety. Nitrogen nutrition of the host influenced the disease incidence. The total and OD phenols were much less in the susceptible variety than in the resistant variety. Further, Bhavani had less quantities of soluble carbohydrates, total nitrogen, ammoniacal nitrogen and protein nitrogen. Phenols accumulated in the infected plants, while the reducing and non-reducing sugars and different nitrogen fractions decreased.