Robert William Keith (1787–1846) was an English musical composer and writer.
Born at Stepney on 20 March 1787, he was the son of Cornelius Keith, organist of St. Peter's, Cornhill, and of the Danish Chapel in Wellclose Street, and the grandson of William Keith, organist of West Ham Church (d. 1800).
From the latter Keith learnt the rudiments of music, and from François Hippolyte Barthélémon and others the violin, harmony, and composition.
[1] Keith compiled instruction-books for pianoforte, flute, and Spanish guitar (by "Paulus Prucilli"), and a violin preceptor, which went through many editions.
He set to music elegiac verses Britannia, Mourn, on the death of the Princess Charlotte Augusta of Wales, 1817; arranged the overture and airs from Der Freischütz as duet for two violins, c. 1830; and edited Favourite Airs with Variations, for the Violin.