The invention discloses an 
underwater acoustic communication balanced decoding method based on a recursive 
chaotic code, and the method comprises: step 1, inputting an information source information sequence into a recursive 
chaos model by a coding sending end, carrying out the recursive 
chaotic coding, generating a symbol 
frame sequence, generating an information sub-frame, and sending the information sub-frame after 
signal modulation to a coding receiving end; step 2, the coding receiving end demodulating the received information subframes to generate a symbol sequence, and generating a joint 
equalization decoding tree according to the number of information fragments in the symbol sequence and the number of information fragments in the information source information sequence; and step 3,the coding receiving end calculating the 
Euclidean distance between the symbol sequence in each 
branch and the symbol sequence which is actually received, selecting the 
branch with the minimum 
Euclidean distance, and marking the 
branch as a decoding result. Through the technical scheme provided by the invention, the 
bit error rate performance of the 
underwater acoustic communication 
system is improved, the influence of strong inter-code 
crosstalk of the 
underwater acoustic channel and the complexity of a joint 
equalization decoding 
algorithm are reduced, and the transmission reliability of the underwater acoustic channel is improved.