The sediments from 12.7 mto 17.4 min the core QG01 which was taken from the west coast of Bohai Bay were analyzed with grain size analysis,XRD and OSL,the characteristics of clay mineral assemblages and used as paleoclimatic proxies were also investigated.The sediments are composed of sandy silt,silty sand,and clayey silt,with the rage 4.11~7.79Phi.The results show that illite-chlorite-kaolinitesmectite is the main clay mineral assemblage.The KI and the ratio values of(illite+chlorite)/(kaolinite+ smectite)are used as paleoclimate proxies.The results show that two proxies can reflect the feature of climate change when the trends of the two proxies are corresponding.On the contrary,when the trends of the two proxies do not correspond with each other,they cannot be used as paleoclimatic proxies since the source of sediments may change.