John Sinclair (20 August 1797 - 22 May 1875) was Archdeacon of Middlesex from 1844 until his death.
The son of Sir John Sinclair of Ulbster, he was educated at Pembroke College, Oxford. He was ordained in 1821. He was appointed Vicar of Kensington in 1842, a post he held while also archdeacon.