Ralph Knott FRIBA (3 May 1878 – 25 January 1929) was a British architect. He was responsible for building the massive 6-storey "Edwardian Baroque" style County Hall building for the London County Council. In 1919 Knott married Ada (née Brown), widow of Sidney James Longden. They had no children. He died suddenly at his Mortlake home in January 1929, aged 50. A bronze plaque to his memory at County Hall was unveiled by the Chairman of the London County Council in June 1932.