To provide a grain drying machine for keeping grains at adequate temperatures for hulling work depending on the amount of grains and the temperature of the grains after completion of a drying process.

When the moisture content of the grains reaches set one after starting the drying process, the drying process is completed. Then, a charged grain amount detecting means 20 detects the amount of charged grains and inputs the detection result to a control part 41. The control part 41 carries out a draft circulating process for a period of time set depending on the amount of the charged grains. In the draft circulating process, changes in the temperature of outside air and in the temperature of the grains are displayed in time series so that whether the grains are at adequate temperatures or not can be determined.