Leonard Grey, 1st Viscount Grane or Graney (1479/1492 – 28 July 1541), known as Lord Leonard Grey prior to 1536, served as Lord Deputy of Ireland from 1536 to 1540.
Leonard Grey was a younger son of Thomas Grey, 1st Marquess of Dorset and Cecily Bonville, Baroness Harington and Bonville.
On receiving instructions from King Henry VIII, Grey commanded an army which he led against Irish rebels who would not acknowledge Henry's supremacy as supreme head of the Church of England, and renounce the Pope. He was said to have been so cruel that he shortened the life of the Deputy, William Skeffington. Grey was created Viscount Grane in the Peerage of Ireland on 2 January 1536.
On 11 July 1537 Grey as Lord Deputy of Ireland visited Galway. This was the first visit of a King's Deputy to the town, and marked the start of closer relations between the town and the Anglo-Irish administration in Dublin. He was lavishly entertained and stayed for seven days.
Grey was accused of allowing the escape of his sister Elizabeth's son, the young Earl of Kildare to France in 1539, which he strenuously denied. Grey was nevertheless tried and attainted of high treason, and subsequently executed at the Tower of London on 28 July 1541 by the orders of Henry VIII.
Grey is said to have married firstly Elizabeth Arundel, widow of Sir Giles Daubeney, and secondly Eleanor Sutton, daughter of Edward Sutton, 2nd Baron Dudley by Cecily Willoughby, daughter and coheiress of Sir William Willoughby; however, according to Lyons it is unclear whether Grey ever married. He is mentioned in the will of his brother, Sir John Grey.