William Borthwick, 4th Lord Borthwick

William Borthwick, 4th Lord Borthwick (died 1542) was a Scottish nobleman.

He succeeded his father William Borthwick, 3rd Lord Borthwick in 1503. Immediately after the battle of Flodden, William, 4th Lord Borthwick, was appointed by the Privy Council of Scotland to the command of Stirling Castle which was ordered to be well fortified, along with the important custody of the infant monarch, King James V of Scotland.

The seal of William, Lord Borthwick, appears on the treaty signed with England on 7 October 1517.

Lord Borthwick married, in 1491, Margaret, eldest daughter of John Hay, 1st Lord Hay of Yester, by whom he had two sons and three daughters: