Control Device And Work Vehicle

A control portion includes a vehicle-position acquiring portion, a field-contour setting portion, a region setting portion, and a display processing portion. The vehicle-position acquiring portion acquires position information indicating a position of the combine harvester traveling on a field. The field-contour setting portion sets a contour of a field on the basis of a plurality of pieces of the position information. The region setting portion sets a region not subject to a work indicating a region which is not a target for the work by the combine harvester inside the field or outside the field on the basis of the contour. The display processing portion causes a field image showing the field and an identification image for identifying the region not subject to the work, to be displayed on a display portion.