Steven Victor Ley CBE FRS FRSC (born 10 December 1945) is Professor of Organic Chemistry in the Department of Chemistry at the University of Cambridge, and is a Fellow of Trinity College, Cambridge. He was President of the Royal Society of Chemistry (2000–2002) and was made a CBE in January 2002, in the process. In 2011, he was included by The Times in the list of the "100 most important people in British science".