Based on geological and archaeological studies, including palaeoreconstruction of the sedimentary environment and AMS 14C dating, a new fishing camp in Chuanganglu Pit, located ~5 km west to the present shoreline on the west coast of Bohai Bay, left by the West Han people was found recently from a buried shelly beach and it was overlayed by 1.6 m thick marine layer which lasted for 700~800 years. Until now, this West Han people ruin which was overlayed by marine layer is the nearest one to the modern shoreline on the west coast of Bohai Bay. Following the mid Holocene marine regression, at least five chenier—linear earthy mound palaeoshorelines existed on the west coast of Bohai Bay. Their forming ages were 6.6~6.2 ka cal BP, 5.5 ka cal BP, 3.3 ka cal BP, 2.4~2 ka cal BP and 0.9 ka cal BP (4650~4250BC, 3350BC, 1350BC, 450~50BC and 1050AD), respectively. Each chenier—linear earthy mound shoreline was a boundary between land and sea in a certain time period, during which its seaward area was ancient sea while its landward depression area was frequently inundated by high waters (both storm surges and spring tides). Of them, the Shanggulin—Qijiafu chenier—linear earthy mound shoreline emerged during the Warring States to West Han Dynasty and dead a thousand years later in the East Jin—North Wei Dynasties. During this period, seaward area was occupied by sea water and landward depressions were frequently influenced by high waters. On the other hand, the West Han ruin at the Chuanganglu site was directly buried by the marine layer. Both of them provided plausible geological evidence for the West Han Transgression existence on the west coast of Bohai Bay.