Sir Eric Herbert Blain (7 May 1904 – 19 November 1969) was a British barrister and High Court judge who sat in the Queen's Bench Division from 1965 until his death.
Educated at Uppingham School and King's College, Cambridge, he was called to the Bar by the Middle Temple in 1927.
During the Second World War, he served with the Suffolk Regiment and the General Staff, reaching the rank of lieutenant-colonel.
The "acknowledged leader of the Parliamentary Bar", Blain was elected a Bencher of the Middle Temple in 1957 and was appointed a Queen's Counsel in 1961.
In 1965, he was appointed to the High Court and was assigned to the Queen's Bench Division, receiving the customary knighthood.