The invention discloses a grain impurity removal drying device. A driving shaft is in bearing rotation connection with a device body, the middle of the driving shaft is fixedly connected with an eccentric wheel, the upper end of the eccentric wheel is in abut joint with the bottom of an inclined screening plate, the inclined screening plate is in sliding connection with a guide groove, the upper portion of the left end of the inclined screening plate is fixedly connected with a plug column, the upper end of the plug column is provided with a guide pipe, the guide pipe communicates with the bottom of a storage box, an impurity discharge channel is formed in the upper end of a wire groove in the right end, and the lower end of the impurity discharge channel is communicated with an impurity chamber; the inclined screening plate drives the plug column to block the guide pipe in a reciprocated manner to enable grains in the storage box to be intermittently discharged, the inclined screeningplate drives grains to slide while the grains vibrate, the grains fall down through leaking holes in the surface of the inclined screening plate, large impurities fall in the impurity chamber throughthe impurity discharge channel, small particle impurities enter the impurity chamber through the filter plate to achieve joint discharge of large and small particle impurities, in the falling processof the grains, the grains make full contact with hot air blown by a fan. The device is reasonable and applicable in structural design, the grain drying effect is greatly improved, meanwhile, the impurity removal effect is good, labor force is saved, and the automation degree is high.