English poet and critic, the younger brother of the poets and essayists Edith and Osbert Sitwell. He is best known for his books on art, architecture, and travel.

Sitwell's poetry—The People's Palace (1918), The Thirteenth Caesar (1924), The Rio Grande (performed 1929, with music by Constant Lambert), Selected Poems (1948), and other volumes—written predominantly in traditional metres, reveals in its mannered style the effect of his interest in the arts and music. More original are his imaginative and interpretative books, of which the first, Southern Baroque Art (1924), was the forerunner of much academic research. His poetic prose is seen at its best in the “autobiographical fantasia” All Summer in a Day (1926) and the gloomily meditative Splendours and Miseries (1943). He succeeded his brother as the 6th baronet on Osbert's death in 1969. For Want of the Golden City (1973) is a series of essays on life and art containing a considerable amount of autobiographical material. A noted traveler, Sitwell said in 1982 that, among the most beautiful sites on earth, he judged Venice to be the best, with Angkor Wat in Cambodia in second place.