A work vehicle includes a vehicle body, at least one obstruction sensor, at least one state sensor, and circuitry. A work device is attachable to the vehicle body. The at least one obstruction sensor is provided on the vehicle body to detect an obstruction to the work vehicle. The at least one state sensor is provided on at least one of the vehicle body and the work device to detect at least one state of the vehicle body and the work device. The circuitry is configured to determine an obstruction detection area based on the at least one state detected by the at least one state sensor, and to determine whether the obstruction exists within the obstruction detection area based on a sensor signal from the at least one obstruction sensor.