Sir Nicholas Grimshaw, CBE (born 9 October 1939) is a prominent English architect, particularly noted for several modernist buildings, including London's Waterloo International railway station and the Eden Project in Cornwall. In late 2004, he was elected President of the Royal Academy.

Born in Hove, East Sussex, Grimshaw inherited an interest in engineering (one of his great-grandfathers was responsible for overseeing the installation of Dublin's drainage and sanitation system, while another built dams in Egypt). He is also reputed to have displayed an early interest in construction; his boyhood interests included Meccano, building tree houses and boats.

He was educated at Wellington College. From 1959 to 1962, he studied at the Edinburgh College of Art before winning a scholarship to attend the Architectural Association School of Architecture in London, where he won further scholarships to travel to Sweden in 1963 and the United States in 1964. He graduated from the AA in 1965 with an honours diploma, and having entered into a partnership with Terry Farrell, he joined the Royal Institute of British Architects two years later in 1967.