PROBLEM TO BE SOLVED: To provide a grain drier capable of suitably performing cleaning operation for efficiently securing the fire prevention without impairing running efficiency in a case of the drying operation by switching the grain type.SOLUTION: A grain drier comprises with the possible selection: drying operation for drying grain to a target water content value; and cleaning operation for discharging the generated dust by the idle operation. The running time every the drying operation is accumulated as an accumulation drying drive time. When the accumulation drying drive time reaches a prescribed limit time, a selection of the cleaning operation can be guided so as to be displayed. The grain drier also comprises type specifying means of target grain of the drying operation. On the basis of the generated dust amount for each type of grain which is obtained separately, by accumulating a conversion drying drive time, which is converted to the drying drive time of predetermined reference grain equivalent to
