What is the name of the paradise ruled by the Queen Mother of the West?

The paradise ruled by the Queen Mother of the West is Kunlun Mountain.

In Chinese mythology, Xiwangmu—the Queen Mother of the West—holds court on the mythological Mount Kunlun, a sacred western mountain imagined as a meeting place between gods and humans. Its palace is described as a perfect paradise, rather than an ordinary earthly settlement.

The Queen Mother is associated with longevity, immortality, and the peaches of immortality. Some traditions place her Jade Pond and peach orchard within or near the Kunlun complex, which can cause confusion between Kunlun Mountain and Jade Pond. Mount Penglai is a different legendary island paradise linked especially with immortals and the search for eternal life.

Her traditions are much older than organized Taoism. References to a Western Mother appear in Shang-dynasty oracle-bone inscriptions, while her role as a dispenser of longevity became especially prominent during the Han dynasty. A famous later story recounts King Mu of Zhou visiting her on Kunlun.