A method for transmitting and extracting a timing signal for use in a multi-carrier parallel data transmission system having the carrier frequencies of channels arranged at baud rate intervals. On a transmitting side, two pilot signals, whose frequency difference is an integral multiple of the baud rate, are inserted outside the signal band of said data transmission system and transmitted to a receiving side. On the receiving side, the frequency difference signal of said two pilot signals is taken out and is frequency-divided to extract a timing signal equal to the baud rate frequency. By this use of two pilot signals, it then becomes possible to transmit and extract a timing signal without sacrificing any of the valuable carriers contained within the data transmission band.