This road surface illumination device is provided with: a vehicle state determination unit (3) for determining the traveling direction of a vehicle on the basis of vehicle information obtained by a vehicle information-acquiring unit (2); and an illumination pattern-selecting unit (4) for selecting, from stored illumination patterns for each traveling direction, an illumination pattern that represents the traveling direction determined by the vehicle state determination unit (3), and emitting the illumination pattern from an illumination unit (7) to a road surface at least in a direction different from the traveling direction. Hence, the traveling direction of the vehicle can be intuitively understood by a person who is outside the vehicle and is in a direction other than the traveling direction.
