Eleftherios Phedias Diamandis (born October 8, 1952) is a Cypriot-Canadian biochemist who specializes in clinical chemistry.
He is Professor & Head of Clinical Biochemistry in the Department of Laboratory Medicine and Pathobiology at the University of Toronto in Toronto, Ontario, Canada.
He is also Division Head of Clinical Biochemistry at Mount Sinai Hospital and Biochemist-in-Chief at the University Health Network, both of which are also located in Toronto.