Abstract: The terraces in western Hainan Island have been measured by using DGPS system. Based on their geomorphic feature, two type terraces are divided. One is marine landform including a sand bank and four terraces. The sand bank is 10 meters high and formed since 5000a. The first terrace is 20 meters high and formed nearly in Holocene. The second terrace is 32~34 meters high and formed in late Pleistocene. The third terrace is 40~42 meters high and formed since nearly 121.8 ka. The fourth terrace is 57~62 meters high and only occurred in a few counties and formed in late mid-Pleistocene. The other is fluvial landform, including four terraces. The first terrace is 20 meters high and formed since 11.4 ka. The second terrace is 34 meters high and formed since 47.2ka. The third terrace is 50 meters high, but the elevation of surface of terrace base is 41 meters, which formed in the early stage of late Pleistocene. The fourth terrace is 71 meters high, but the elevation of surface of terrace base is 60 meters, which formed in the late stage of middle Pleistocene. The second terrace is well developed. Since Late Pleistocene, the whole region accelerates uplifting. Furthermore, the activity of Wangwu-Wengjiao fault may be weaker.

Key words: Hainan Island, Neotectonic, Terrace, Wangwu-wengjiao fault