To construct information environment that augments the real world, there is an important theme that is realization of embedding information into a certain area and receiving it naturally. To develop these systems, it is necessary to announce the existence of additional information and intuitive connection of real world and them. Approaches that use marker-type indicators like AR marker [Kato and Billinghurst 1999] which is significant for the camera recognition but insignificant for human have exiguous intuitiveness. On the other hand, when applying wireless communication technologies like RFID or infrared light [Nishimura et al. 2004], which we cannot sense the existence of the information, we need another sign that indicates the existence of the information to embed information to certain areas. Toward these problems, we propose a novel system named SteganoSonic that embeds digital data into the sound outputted from parametric speakers. This system, with a speaker which has strong directivity, can send audible sound to certain area and embed additional information into the sound which is caught by a receiver. Users can find the existence of additional information by hearing the sound, receive additional information at the same time.