Abstract: In order to improve the language comprehension of hearing-impaired patients under complex scenarios, a binaural sound localization algorithm for hearing aids based on auditory bionics is proposed. Firstly, according to the property of cochlear frequency-division and hearing masking, the sound is divided into multi-channel signals. Tile interaural time differences (ITD) of the sensitive frequency bands are taken as the localization cues. Then, the real ITD is extracted based on the Haas effect. Finally, the HRTF model is used to convert the ITD to the sound position. In order to improve the robustness, a multi-channel weighting combined algorithm is adopted to compute the position of the non-speech signal. From the simulation and scenario experiments, results show that the algorithm has strong anti-interference and high positioning accuracy. Furthermore, in the speech intelligibility test for seven subjects, the proposed speech enhancement algorithm improves 3~5 dB than other algorithms for hearing aids.