PURPOSE: To provide a synchronous word detection system capable of surely detecting a synchronous word even when the same data as the synchronous word are present in the data in reception burst signals and quickly establishing synchronization.

CONSTITUTION: At the time of detecting the synchronous word, a channel identification code placed behind the synchronous word is monitored by a channel identification code comparing and judging device 4. When the channel identification code placed behind the synchronous word is detected and judged in the channel identification code comparing and judging device 4 following the detection of the synchronous word by a synchronous word comparing and judging device 2, a synchronous word detection signal is outputted as the detection of the synchronous word.