Andrew Gray, 1st Lord Gray (c. 1390–1469) was a Scottish nobleman, politician and diplomat. He was succeeded to the title by his grandson.
He was the only son of Sir Andrew Gray (d. 1445) of Fowlis, Perthshire, by his first wife Janet, daughter of Sir Roger de Mortimer, whom he married in 1377.
In 1424 he was accepted by the English government as one of the hostages for the payment of the ransom of James I of Scotland, apparently in place of his father, whose estate was estimated at the time as being worth six hundred merks annually. His father presented a letter to the English government, in which the hostage is said to be his only son and heir, promising fidelity on behalf of his son, and also that he would not disinherit him on account of his acting as a hostage. He was sent to Pontefract Castle, and afterwards committed to the Tower of London, where he remained until 1427, when he was exchanged for Malcolm Fleming, son of the laird of Cumbernauld.
In 1436, he accompanied Princess Margaret, daughter of James I, to France, for her marriage to the Dauphin Louis. In 1449 he was appointed part of a committee of the Estates to examine previous acts of Parliament and general councils, and report to Parliament on their existing validity. On various occasions between 1449 and 1460 he was employed as one of the Scottish ambassadors to negotiate treaties of peace with England, and appointed as a general conservator of these treaties. He briefly acted as a Warden of the Marches.
In 1451, along with the abbot of Melrose Abbey, he received a safe-conduct to allow him to make a pilgrimage to Canterbury, and in 1452 he became Master of the Household to James II.
On 26 August that year he was granted permission to build a castle on any part of his lands, and he built Castle Huntly on his estate of Longforgan in the carse of Gowrie (not to be confused with the older Huntly Castle, in Aberdeenshire). This castle, long the residence of the family, was sold to the Earl of Strathmore in 1615, and the name changed to Castle Lyon. In 1777, it was repurchased by George Paterson, who married Anne Gray, daughter of the 11th Lord Gray, and restored the original name.