John Campbell (born March 1766 in Edinburgh, Scotland – 4 April 1840 Kingsland, London), was a Scottish missionary and traveller.

His consuming interest in Christian philanthropy led him to preach widely in neglected villages and hamlets, promote the establishing of numerous Sunday schools and found societies like the Magdalene asylum to help prostitutes in Edinburgh and Glasgow.

His return trip went via Klaarwater, Pella and the Kamiesberge, arriving in Cape Town at the end of October.

He wrote an account of this trip as "Travels in South Africa, undertaken at the request of the Missionary Society" and it was published on his return to London in 1815.

Campbell once more ventured into the interior, leaving Cape Town in January 1820 and travelling as far north as Mosega in Barotseland, on which journey he also came across the large settlement of Kaditshwene near the Limpopo River.