The present invention, when it is estimated that a device that can receive a large-sized advertisement is present within a communication area, transmits advertisement packets of that size. A communication device of this invention comprises a first transmission unit that transmits a first advertisement packet, using a first frequency band, a determination unit that, upon receiving a request packet in response to the first advertisement packet, determines whether or not an external device that can receive the second advertisement packet whose size is larger than that of the first advertisement packet is present within a communication area, based on the request packet, and a second transmission unit that, if the determination result indicates the presence, transmits a second advertisement packet, using a second frequency band different from the first frequency band.