The invention discloses a parallel combined spread spectrum underwater acoustic communication method of an interleaved Gold mapping sequence. The method comprises the following steps: step 1) selecting r information sequences from a spread spectrum sequence set according to a data-spread spectrum sequence mapping table at a signal transmitting end to perform multichannel interleaving to generate an information mapping sequence, selecting a sequence that is not related to the sequences in the spread spectrum sequence set as a synchronizing sequence, transmitting the synchronizing sequence andthe information mapping sequence into an underwater acoustic channel after performing quadrature modulation; and step 2) demodulating received signals to a complex baseband at a signal receiving end,performing Doppler compensation to obtain a received signal sequence, then obtaining L multichannel parameters by using the operation results of the synchronizing sequence and the received signal sequence, performing de-interleaving and multichannel merging on the received signal sequence by using these parameters, and performing operation to obtain r sequences, respectively performing maximum value calculation judgment on the r sequences by using M paths of correlators to obtain judgment symbols of transmitting sequences, and then obtaining sequence numbers of the transmitted r information sequences.