Abstract: Devoted to the study of underwater blind channel estimation, this paper proposed a method combined with high precision time-delay estimation to handle channel estimation, using an emitted source signal and single/multiple hydrophones. The received signal is used for source signal reconstruction by means of signal-dependent TF distribution, in association with instantaneous frequency estimation and TF inversion. Finally the shallow-water channel estimation is achieved via WRELAX technique by use of the received signal and the estimated source signal. The results of numerical simulation and experimental test from the real data taken in a South China Sea trial have proved satisfactory. It is shown that the proposed method provides high precision underwater channel estimation.