A speech encoding/decoding method using an encoder working at very low bit rates, comprises a learning step enabling the identification of the representatives of the speech signal; and an encoding step to segment the speech signal and determine the best representative associated with each recognized segment. The method also comprises at least one step for the encoding/decoding of at least one of the parameters of the prosody of the recognized segments, e.g., the energy, pitch, voicing, and/or length of the segments, by using a piece of information on prosody pertaining to the best representatives. The method can employ a bit rate of lower than 400 bits per second.