Angus McLagan (1891 – 4 September 1956) was a New Zealand politician of the Labour Party.
McLagan represented the Riccarton electorate from 1946 to 1956, when he died. He was a cabinet minister from 1946 to 1949 in the First Labour Government.
He had previously been appointed to the Legislative Council in 1942, and he resigned from it in 1946.
He was married to Sophie McLagan (her second marriage). They had two daughters (Cissie Agnes McLagan, Margaret Bridget McLagan) and two sons (Angus and John Campbell (Jock) McLagan).
The McLagan Family had a bach in the lower Boyle River area of the Lewis Pass in North Canterbury, which was built on a (crown peppercorn rental) lease property. The McLagan bach was moved and rebuilt by Jock McLagan on an upper plateau (just above the Boyle River) in the early 1970s. Often referred to as "the hut", the bach had been given the name of "Toad Hall" by J.C. McLagan. It formed the centre of McLagan and Sullivan family holidays for many years, subsequent along with the Dean's family (early Canterbury settlers). The Deans family also had a bach on the same river flat just above the Boyle River. Fishing and hunting were the main holiday pursuits of both families at the time.
Angus McLagan collected a large number of ex-parliamentary library books (which were officially discarded) and other records, primarily books written in Latin (e.g. Homer's travels and a leather bound copy of the Iliad printed in the early 19th century), which remained with Sophie McLagan until her death in 1979. Angus McLagan died one year to the day before the birth of his first grandchild (4 September 1957, John Angus Sullivan), first son of Cissie Agnes (née McLagan) and John Henry Sullivan (ex Middlesex, England) followed by Alastair Maurice Sullivan (1959) and Robyn Margaret Bridget Sullivan (1961).