To provide a grain discharger that has a smoothly retractable discharge auger, prevents foreign matters from entering in between a stationary auger cylinder and a mobile auger cylinder, reduced cost, and allows reliable and smooth retractable motion and actuation.

This grain discharger includes a transverse discharge auger 6 dividedly formed of a stationary auger 7 connected to a vertical grain elevator 5 functioning to discharge the grains in a grain tank 4 and a mobile auger 8 retractably attached to the stationary auger 7; wherein the stationary auger cylinder 9 of the stationary auger 7 and the mobile auger cylinder 14 of the mobile auger 8 are mutually superposed with their diameters made different from each other, the mobile auger cylinder 14 is provided with a plurality of rollers 20 circumferentially, and each of the rollers 20 is made to butt on a guide member 25 provided on the outer circumference of the stationary auger cylinder 9.