A time synchronization system includes a first wireless device and a second wireless device. A wireless unit of the first wireless device wirelessly transmits timing information and time information separately, the time information being acquired from a first clock and relating to a transmission time when the timing information was transmitted. A wireless unit of the second wireless device receives the wirelessly transmitted timing information and time information separately. A correction unit of the second wireless device corrects s a second clock on the basis of a reference time indicated by the second clock at a time when the wireless unit received the timing information, and a transmission time obtained from the time information.