The embodiment of the invention relates to the technical field of communication, and particularly relates to a method, a device and a system for ring back tone distribution so as to automatically deploy color ring back tones for calling platforms supporting different ring back tone formats. In the embodiment of the invention, a ring back tone corresponding to a ring back tone identifier is acquired according to the ring back tone identifier, according to ring back tone distribution information of each calling platform in N calling platforms respectively, the ring back tone format is converted to the ring back tone format supported by the corresponding calling platform; at least two calling platforms in the N calling platforms support different ring back tone formats; and the ring back tones after format conversion are respectively sent to the corresponding calling platforms. As the ring back tone formats can be converted to the ring back tone formats supported by corresponding calling platforms according to the ring back tone distribution information of each calling platform in N calling platforms, the ring back tones after format conversion are further sent to the corresponding calling platforms, and the purpose of automatically deploying color ring back tones for the calling platforms supporting different ring back tone formats is thus realized.