The invention provides a synchronous playing control system and method of wireless multi-channel sound. The synchronous playing control system comprises a main control device having a function of triggering action according to synchronization information of wireless connection, and a controlled device, the main control device is connected with a sound source, the controlled device is connected with the sound source via the main control device, the main control device and the controlled device separately comprises a playing subsystem and a wireless transmission subsystem, and the playing subsystem comprises a microphone used for obtaining audio signals, an audio data processor used for processing audio data, an audio amplifier and a horn; the wireless transmission subsystem comprises a wireless modem and a radio frequency device; and on the basis of the original wireless connection technology, the synchronous playing control of multi-channel sound is achieved by the synchronization information of the wireless connection, and meanwhile the wireless multi-channel sound is kept synchronously all the time by using a synchronization information transmission mechanism.