To provide a cooling system of grains which makes it possible to incorporate in a check bottle (a small-sized silo as a buffer) a heat exchanger conducting efficient cooling with high energy efficiency in a short time and prevents reduction of the amount of wheat stored temporarily in the check bottle, as far as possible, by the incorporation of the heat exchanger in the check bottle.

The cooling system of grains has air supply equipment which introduces cooling air, the main body of the heat exchanger which makes the air pass among the grains and conducts heat exchange between the grains and the air and air discharge equipment which discharges the air of which the temperature has risen. The system is so constituted that the air supply equipment and the air discharge equipment are interlocked so that the quantity Qi of the air supplied by the air supply equipment and the quantity Qo of the air discharged by the air discharge equipment may conform with each other substantially.