The present disclosure relates to a method by which a third device transmits audio data in a short-range wireless communication system, and to an apparatus therefor. According to the present specification, the method by which a third device transmits audio data in a short-range wireless communication system comprises the steps of: transmitting, to at least one device, a first advertisement message for providing a broadcast audio data streaming service; transmitting, to the at least one device, a second advertisement message related to synchronization of an audio data output time point, wherein the second advertisement message includes force delay information for synchronizing a time point at which the audio data is output from each of the at least one device; and transmitting the audio data to the at least one device, wherein the time point at which the audio data is output from each of the at least one device is determined on the basis of the force delay information.