The One Tree is a fantasy novel by American writer Stephen R. Donaldson, the second book of the second trilogy of The Chronicles of Thomas Covenant series.

Following the vision he received from the Clave at Revelstone, Thomas Covenant seeks to fix the corruption of the Land after the Staff of Law's destruction.

From the Land, the Giant-ship sails to the home of the Elohim that Linden perceives are an embodiment of Earthpower, the source of magic.

After suffering severe damage in a storm, in which Findail refuses to help, the ship arrives at the port city of the Bhrathair, a militaristic – but also wealthy and civilized – people living at the edge of a great desert.

Brinn, Covenant's Haruchai bodyguard, sacrifices himself in a duel with the Tree's Guardian ak-Haru Kenaustin Ardenol.

When Seadreamer makes the attempt himself, he is killed: he has disturbed the Worm of the World's End, which sleeps beneath the Tree and whose "aura" serves as a defense mechanism.

With her help, he is able to contain his power, but at the price of the Isle of the One Tree sinking beneath the ocean as the earth heaves with the movements of the Worm of the World's End settling back from disturbance into slumber.