John St Aubyn

Sir John St Aubyn, 4th Baronet (12 November 1726 – 12 October 1772), of Clowance and St Michael's Mount, was a British Tory politician.

Biography St Aubyn was the only son of Sir John St Aubyn, 3rd Baronet and Catherine Morice, daughter and coheiress of Sir Nicholas Morice, 2nd Baronet. He was educated at Oriel College, Oxford, entering the college in 1744.

In 1747, St Aubyn was returned as a Tory Member of Parliament for Launceston on the interest of his uncle, Sir William Morice, 3rd Baronet. At the 1754 British general election, however, he was not given a candidacy in the seat by his Whig cousin, Humphry Morice. A 1758 by-election in the seat following the death of Sir George Lee saw St Aubyn briefly returned to the Commons for Launceston. In 1761, St Aubyn was elected to the county seat of Cornwall as a Tory. He held the seat the seat until his death in 1772, throughout which time he voted with the opposition.