Frederick Craig Riddle OBE (20 April 1912 – 5 February 1995) was an important British violist. He was considered to be in the line from Lionel Tertis and William Primrose, through to the violists of today such as Lawrence Power.

Frederick Riddle was born in Liverpool in 1912. He studied at the Royal College of Music (RCM) in London 1928-33. He had a solo career while playing with the London Symphony Orchestra 1933-38, then in 1938 was appointed principal viola with the London Philharmonic Orchestra. He was a professor of the RCM from 1948. In 1953 he succeeded Harry Danks as principal violist of the Royal Philharmonic Orchestra.

Riddle was distinguished as a chamber music player and a concerto soloist. He made the first recording of William Walton's Viola Concerto, on 6 December 1937, with the composer conducting. He was recommended for this recording by Lionel Tertis. He made some revisions to the concerto, with Walton's approval. Although Walton conducted the work many times with leading soloists such as Tertis and William Primrose, the interpretation he liked above all others was that of Frederick Riddle. He also performed the work in concert under Beecham.

Works that Frederick Riddle premiered included:

Malcolm Arnold's Viola Sonata, in the 1940s.

Arthur Benjamin's Viola Concerto, in 1948, with the Hallé Orchestra under Sir John Barbirolli.

Giorgio Federico Ghedini's Viola Concerto, in 1953, with Beecham conducting.

Howard Blake's Prelude for Solo Viola, Op. 402, in 1980