Robert Buchanan (1802–1875) was a Scottish Presbyterian minister and historian who served as Moderator of the General Assembly to the Free Church of Scotland in 1860/61.

He had correspondence with several notable figures of the day over many years: Lord Aberdeen; Sir Robert Peel; Thomas Chalmers from 1834 to 1845; and George Combe from 1821 to 1827.

He was ordained in the Church of Scotland in 1826 in Gargunnock and translated in 1829 to Saltoun in East Lothian, replacing Rev Dr Gilbert Burnet.

In 1838 it was Buchanan who chaired the debate on the "Auchterarder question", regarding the ability of a congregation to refuse a minister proposed by the local patron.

[6] In 1860 he succeeded Very Rev William Cunningham as Moderator of the General Assembly, the highest position in the Free Church.