Sir John Anstruther, 4th Baronet and 1st Baronet PC (27 March 1753 – 26 January 1811) was a Scottish politician. The second son of Sir John Anstruther, 2nd Baronet, he was knighted in 1797, raised to the Baronetage of Great Britain in 1798, and also succeeded as 4th Baronet in the Baronetage of Nova Scotia on the death of his elder brother, Philip, in 1808. He served as Member of Parliament for Anstruther Burghs, in Fife, from 1783 to 1790, 1796–1797 and 1806–1811, and for Cockermouth, in Cumberland, from 1790 to 1796. He was appointed a Privy Counsellor in 1806.