John Newton (; 4 August [O.S. 24 July] 1725 – 21 December 1807) was an English evangelical Anglican cleric and slavery abolitionist. He had previously been a captain of slave ships and an investor in the slave trade. He served as a sailor in the Royal Navy (after forced recruitment) and was himself enslaved for a time in West Africa. He is noted for being author of the hymns Amazing Grace and Glorious Things of Thee Are Spoken.

Newton went to sea at a young age and worked on slave ships in the slave trade for several years. In 1745, he himself became a slave of Princess Peye, a woman of the Sherbro people in what is now Sierra Leone. He was rescued, returned to sea and the trade, becoming Captain of several slave ships. After retiring from active sea-faring, he continued to invest in the slave trade. Some years after experiencing a conversion to Christianity, Newton later renounced his trade and became a prominent supporter of abolitionism. Now an evangelical, he was ordained as a Church of England cleric and served as parish priest at Olney, Buckinghamshire, for two decades and wrote hymns.

Newton lived to see the British Empire's abolition of the African slave trade in 1807, just months before his death.