Arthur David Waley CH CBE (né Schloss, 19 August 1889 – 27 June 1966) was an English orientalist and sinologist who achieved both popular and scholarly acclaim for his translations of Chinese and Japanese poetry. Among his honours were appointment as Commander of the Order of the British Empire in 1952, receiving the Queen's Gold Medal for Poetry in 1953, and being invested as a Member of the Order of the Companions of Honour in 1956.

Although highly learned, Waley avoided academic posts and most often wrote for a general audience. He chose not to be a specialist but to translate a wide and personal range of classical literature. Starting in the 1910s and continuing steadily almost until his death in 1966, these translations started with poetry, such as A Hundred and Seventy Chinese Poems (1918) and Japanese Poetry: The Uta (1919), then an equally wide range of novels, such as The Tale of Genji (1925–26), an 11th-century Japanese work, and Monkey, from 16th-century China. Waley also presented and translated Chinese philosophy, wrote biographies of literary figures, and maintained a lifelong interest in both Asian and Western paintings.

A 2004 profile by fellow sinologist E. Bruce Books called Waley "the great transmitter of the high literary cultures of China and Japan to the English-reading general public; the ambassador from East to West in the first half of the 20th century", and went on to say that he was "self-taught, but reached remarkable levels of fluency, even erudition, in both languages. It was a unique achievement, possible (as he himself later noted) only in that time, and unlikely to be repeated."

Arthur Waley was born Arthur David Schloss on 19 August 1889 in Tunbridge Wells, Kent, England. The son of an economist, David Frederick Schloss, he was educated at Rugby School and entered King's College, Cambridge, in 1907 on a scholarship to study Classics, but left in 1910 due to eye problems that hindered his ability to study.

Waley briefly worked in an export firm in an attempt to please his parents, but in 1913 he was appointed Assistant Keeper of Oriental Prints and Manuscripts at the British Museum. Waley's supervisor at the museum was the poet and scholar Laurence Binyon, and under his nominal tutelage, Waley taught himself to read Classical Chinese and Classical Japanese, partly to help catalogue the paintings in the museum's collection. Despite this, he never learned to speak either modern Mandarin Chinese or Japanese and never visited either China or Japan.

Waley was of Ashkenazi Jewish ancestry. He changed his surname from Schloss in 1914, when, like many others in England with German surnames, he sought to avoid the anti-German prejudice common in Britain during the First World War.

Waley entered into a lifelong relationship with the English ballet dancer, orientalist, dance critic, and dance researcher Beryl de Zoete, whom he met in 1918, but they never married.

Waley left the British Museum in 1929 to devote himself fully to writing and translation, and never held a full-time job again, except for a four-year stint in the Ministry of Information during the Second World War. In September 1939, he had been recruited to run the Japanese Censorship Section at the Ministry of Information. Assisted by Captain Oswald Tuck RN, he was responsible for checking the dispatches of Japanese journalists in London, private mail in Japanese and intercepted diplomatic signals from the Japanese Embassy in London.