James Blair Leishman, FBA (8 May 1902 – 14 August 1963) was a British scholar of English literature and a translator of German poetry.
The son of a merchant, Leishman was schooled at Earnseal School and at Rydal Mount in Colwyn Bay before studying classics at St John's College, Oxford; he completed a BLitt in English in 1929.
He remained there until 1946, when he moved to the University of Oxford to be a full lecturer; he was promoted to a senior lectureship two years later.
He was also a lecturer (1948–60) and senior research fellow (from 1960) at St John's College, Oxford.
He died after falling during a walk in Switzerland in 1963, the same year that he had been elected a fellow of the British Academy.