Archibald Campbell Colquhoun was a Scottish politician and lawyer.
The son of John Campbell of Clathick, he took the surname Colquhoun in 1804 on inheriting the estate of Killermont, Dunbartonshire. He married, in 1786, Mary-Anne Erskine . He became an advocate in 1768, was a Member of Parliament for Elgin Burghs from 1807 to 1810 and for Dunbartonshire from 1810 to 1820. He served as Lord Advocate from 1807 to 1816 and as Lord Clerk Register from 1816 to 1820. He was a partner in the Thistle Bank of Glasgow.
He died, after a few days' illness, at Hartham, the seat of his son-in-law, Walter Long, on the 8th of December 1820.