A work vehicle includes a memory, a sensor, circuitry, and a display. The memory is to store a target travel route in a work field. The sensor is to detect an actual travel track of the work vehicle to find a traveled portion of the target travel route, along which the work vehicle has traveled. The circuitry is configured to calculate an index value indicating a degree of a deviation of the actual travel track from the target travel route. The display is to display the traveled portion such that a display pattern to display the traveled portion is changed according to the index value.