The effect of thermal energy storage on deep bed grain drying is studied. The rate of evaporation of moisture and humidity of drying air are analysed with time of the day for different depths of bed, heat capacity of storage material and flow rate. The effect of thermal storage is also studied on the fluid temperature, grain temperature and on the overall performance of the system. A parametric study has been done for a typical day of the month of June for climatic conditions in Delhi. It has been observed that the bed moisture content decreases with time of day unlike the humidity of the drying air and grain temperature also decreases with heat capacity.