Jay M. Cohen is a retired Rear Admiral of the United States Navy and former Under Secretary of Homeland Security for Science and Technology of the United States Department of Homeland Security. He entered the Navy in 1968 as an ensign after graduation from the United States Naval Academy. His last assignment was (20th) Chief of the Office of Naval Research and retired on February 1, 2006. Cohen was sworn in as Under Secretary at the Department of Homeland Security on August 10, 2006.