A control device includes a first acquiring portion, a second acquiring portion, a generating portion, and a display processing portion. The first acquiring portion acquires first information on a work target region in which a work vehicle travels and works in a field. The second acquiring portion acquires second information on a worked region in which the work vehicle has worked. The generating portion generates progress information indicating progress of a work by the work vehicle on the basis of the first information and the second information. The display processing portion causes an index indicating the progress information to be displayed on the display portion.