David Wemyss, 2nd Earl of Wemyss (6 September 1610 – July 1679) was an army officer.
Only son of John Wemyss, 1st Earl of Wemyss and Jean Gray (d. 1640), daughter of Lord Gray.
As Lord Elcho, a title he held between 1633 and 1649, he commanded a regiment of Fife infantry in the Scottish army which reached Newcastle upon Tyne in August 1640. On 1 September 1644, at the head of about 6000 men, he was routed by Montrose at Tippermuir, and in August 1645, as supernumerary commander to Lieutenant-General William Baillie, again suffered defeat by Montrose's forces at Kilsyth.
He married three times:
He died in 1679 at Wemyss Castle in Fife, whose estate he had done much to develop.