As sprinklers systems are widely adopted as fire fighting devices in buildings, it is necessary to develop quantitative models for investigation of the influence of sprinklers on fire development. A fire zone model which includes the cooling effect of sprinklers is developed. Heat transfer from the smoke layer to sprinkler water spray was considered as an additional heat loss term in energy balance equation. In the absence of a sprinkler, the predicted temperature of this model matched that of CFAST6.0, while when sprinkler effects were included, the model predicted the temperature profile of the smoke layer with good agreement with published experiments. This model was applied to a hypothetical compartment fire. Results showed that a higher heat release rate of fire led to a significant decrease in smoke temperature following sprinkler activation, while only a small decrease in smoke layer temperature is predicted when increasing sprinkler pressure from 0.05MPa to 0.1MPa.