Henry David Erskine, 10th Earl of Buchan FRS (17 April 1710 – 1 December 1767), styled Lord Auchterhouse until 1745, was a Scottish peer.
Buchan was the eldest surviving son of David Erskine, 9th Earl of Buchan, by Frances, daughter of Henry Fairfax. He was elected a Fellow of the Royal Society in 1734. A freemason, he was Grand Master of the Grand Lodge of Scotland between 1745 and 1746.
Lord Buchan married Agnes, daughter of Sir James Steuart, 7th Baronet, on 31 January 1739. They had six children:
Lord Buchan died at Walcot, Somerset, in December 1767, aged 57, and was succeeded in the earldom by his second but eldest surviving son, David. The Countess of Buchan died at Edinburgh, Scotland, in December 1778, aged 61.