A heat dissipation device with a function of communication includes a conductive substrate, a first conductive sidewall, a second conductive sidewall, a plurality of heat sink elements, and a feeding element. The heat sink elements have different lengths, and they are positioned between the first conductive sidewall and the second conductive sidewall. The first conductive sidewall, the heat sink elements, and the second conductive sidewall are respectively coupled to the conductive substrate. The feeding element is coupled to a signal source. An antenna structure is formed by the feeding element, the conductive substrate, and the heat sink elements.