In　order　to　improve　the　performance　of　source　localization　in　noisy　and　reverberant　environments,　a　novel　time　delay　estimation　(TDE)　method　was　proposed.　This　method　is　called　acoustical　transfer　function　ratio　based　on　statistical　model　(ATFR-SM).　In　the　proposed　algorithm,　the　noise　reduction　method　based　on　the　statistical　model　was　adopted　to　reduce　the　effect　of　noise　on　acoustical　transfer　Function　(ATF).　In　the　ATF　method,　the　power　spectral　density　(PSD)　was　smoothed　and　whitened　to　reduce　the　effect　of　reverberations.　voice　activity　detection　(VAD)　was　used　to　distinguish　the　speech　period　from　the　noise　period,　and　the　TDE　was　performed　in　the　speech　period　to　improve　the　estimation　accuracy.　Moreover,　the　proposed　TDE　method　and　the　linear　closed-form　method　for　source　localization　were　combined　to　constitute　a　source　localization　system.　The　results　of　performance　evaluation　show　that,　in　both　the　noisy　and　reverberant　conditions,　the　lower　percentage　of　abnormal　points　(PAP)　and　lower　root　mean　square　error　(RMSE)　can　be　achieved　by　the　proposed　TDE　method　than　those　of　the　reference　methods.　Meanwhile,　the　source　localization　has　higher　accuracy　than　the　reference　methods.