Sir Nicholas Throckmorton (or Throgmorton) (circa 1515/1516 – 12 February 1571) was an English diplomat and politician, who was an ambassador to France and played a key role in the relationship between Elizabeth I and Mary, Queen of Scots.
Nicholas Throckmorton was the fourth of eight sons of Sir George Throckmorton of Coughton Court, near Alcester in Warwickshire and Katherine, daughter of Nicholas Vaux, 1st Baron Vaux of Harrowden and Elizabeth FitzHugh, the former Lady Parr. Nicholas was an uncle of the conspirator Francis Throckmorton. He was brought up in the households of members of the Parr family, including that of his cousin Catherine Parr, the last queen consort of Henry VIII. He got acquainted with young Lady Elizabeth when he was serving in the household of the dowager queen and her new husband Thomas Seymour, 1st Baron Seymour of Sudeley and became a close confidant. In his youth, he also became favourable to the Protestant Reformation.
After the execution of Lord Thomas Seymour in 1549 and the downfall of Protector Somerset later in the year, Throckmorton managed to distance himself from those affairs and eventually became the part of the circle of John Dudley, 1st Duke of Northumberland and confidant of the young king Edward VI.
He sat in Parliament from 1545 to 1567, initially as the member for Maldon and then in 1547 for Devizes (a seat previously held by his brother Clement Throckmorton). During the reign of Edward VI, he was in high favour with the regents.