There are generally sand barriers of Late Pleistocene Epoch( old sand barrier) along Guangdong coast, on its top and nearby, palaeocoast dunes were often generated and eolian old red sand is distributed. It has been recognized by features that the old sand barrier can change river’s course, form tombolo, its size is main middle sand and coarse sand, contains grail and shelfish in the sand layer etc. and the old sand barrier is marine but eolian. It has been recognized by features that the old sand barrier and sand barrier of Holocene Epoch exist generally by side and are similar height below 10m, height at top of Q32 marine clay under the old sand barrier is zero metre or so, width of marine-erosion platform formed solid rock in sites in Guangdong is tens metres etc. the high sea level at middle period of Late Pleistocene Epoch approaching now sea level comparatively accords with actual situation in Guangdong.