Abstract: End-member model is used in the inversion of high resolution grain size data sequences of No.30 sediment core sampled in the inner shelf of East China Sea. The result shows the data can be reproduced by three end-members(EM). Based on the grain size frequency curves and acquired knowledge, we come to a conclusion that EM1 represents fine modern hemipelagites, EM2 represents coarse modern hemipelagites, and EM3 represents sediment transport from the relict sediment district. Then we analyzed the hydrodynamic environment of the district and concluded that the EM2/(EM1+EM2) sequence represented the variation of coast-wide current of the East China Sea and the variation of East Asian winter monsoon and China temperature. Through comparison with about a hundred year record of East Asian winter monsoon index, China temperature variation curves inferred by ZHU Ke-zhen, and East China winter temperature variation curves inferred by GE Quan-sheng, we found this proxy corresponds very well with the sequences mentioned above. This climate proxy sequence shows a brief period of cold time during 780-920AD and a long period of warm time during 600-1100AD presumed by ZHU Ke-zhen, and the variation of this sequence during the last hundred years is obvious, showing the influences of human being activities.