The Elm Decline took place in 5000 a BP in Northwest Europe is an abrupt environmental event during the Holocene.It has been considered as the natural record of a catastrophic changes and taken as a marker of the boundary between the Atlantic and the Subboreal since it was identified on the Holocene pollen diagrams in the 1930s.Because it happened Just at the time when Neolithic agriculture was initiated locally,it is then thought as the record of human impact,a mile-stone.in the course of the evolution of human-environment relationship. The Elm Decline remains to be an arguable topic even though it has been extensively studied by Quaternary palaeoecologists,archaeologists and(14)C chronologists for over 60 years. This paper intends to make an overall review on the progress in the studies of the Elm Decline in Northwest Europe,and also to introduce the work done in China in the purpose of promoting the research into the Holocene environmental changes and the human-environmental relationship in China.