Abstract: A highly reliable odor communication system which cannot be influenced by the natural condition and phenomenon and does not have a limit of the distance for sending odor signals. In the odor communication system, a data transmission system has an odor analysis unit for measuring humidity, temperature, mass, and odor constituents of an odor source and a data receiving unit has an odor emission unit for emitting an odor based on humidity, temperature, mass, and constituents of the odor, information of which is transmitted from the data transmission system.