Gyokuon-hōsō was the recorded radio broadcast in which Emperor Hirohito announced Japan's surrender to the public.
The broadcast aired at noon Japan Standard Time on 15 August 1945. Hirohito read the Imperial Rescript on the Termination of the War, announcing that Japan had accepted the terms of the Potsdam Declaration. It was the first time many Japanese people had heard the emperor's voice.
The recording was difficult for many listeners to understand because Hirohito used formal Classical Japanese and the audio quality was poor. The announcement did not use the straightforward modern phrase “Japan surrenders”; instead, it employed courtly and indirect language. The public nevertheless understood that the war was ending.
Gyokuon-hōsō literally refers to the emperor's voice broadcast. It is different from the Japanese Instrument of Surrender, which was the written document signed aboard USS Missouri on 2 September. The broadcast announced the decision; the ceremony formalized it.