Abstract: Based on AMS 14C and optical stimulated luminescence dating of core TLG01 from Tielu Harbor of Sanya in southern Hainan Island, this study comprehensively analyzes lithology, sediment grain size, color index, marine macrofossil and foraminifer indexes. The upper marine deposit belonging to the Holocene is thin that is interpreted as tidal sand flat. Whereas, the lower marine deposits, as thick as 38 m, are dated to MIS 5e and 5d according to optical stimulated luminescence dating. The late Pleistocene transgression-regression sequences are as follows: tidal sand flat-subtidal-tidal mud flat-tidal sand flat. The species of Mollusca living in deep-water condition are identified in late Pleistocene marine layer. The species identification and their related habitats make possible to restore the sedimentary facie. In MIS 5e, the content of silt and clay sharply increased followed by a decrease trend at MIS 5d. Sediment grain size, foraminifera abundance and sediment color index L* show that the highest sea level appeared at the beginning of MIS 5e, while from MIS 5e to MIS 5d, the sea level was lowered, accompanied by the increase in terrestrial coarse sand, indicating relative low sea level toward MIS 5d. The triangular plots of interglacial periods MIS 1 and MIS 5 are respectively consistent with modern surface sediments from the island intertidal zone of Zhanjiang and the South China Sea.

Key words: the Hainan Island, MIS 5, sedimentary facies, sea level change index