The invention relates to a real-time data transmission method, and more particularly to a real-time data transmission method using a Frequency Hopping Spread Spectrum (FHSS) in which a frequency channel, which causes no interference in real-time data transmission, is found to transmit data. In this method, when data is transmitted in real time through a setting channel, a channel in good state is acquired after a setting time through comparison with a test channel and, to prepare for interference that may occur during data transmission, the setting channel is previously changed to another channel before interference occurs, so that real-time data is transmitted while maintaining the continuity of data transmission, thereby minimizing data loss.