Final Fantasy XI: Seekers of Adoulin is the fifth full expansion pack for Final Fantasy XI, and the first full expansion for Final Fantasy XI in over 5 years after Wings of the Goddess. Seekers of Adoulin is set in the western continent of Ulbuka and features new jobs, story, areas, quests and gameplay systems.

PlayStation 2 support for Seekers of Adoulin is only available in Japan. Although Square Enix is not dropping PlayStation 2 support for Final Fantasy XI as a whole, Seekers of Adoulin content will not be accessible on Final Fantasy XI for PlayStation 2 outside of Japan.