The Temple of the Jade Mountain (Vietnamese: Đền Ngọc Sơn) is located on Hoan Kiem Lake in central Hanoi, Vietnam.
Being built on the Jade Islet and dedicated to Confucian and Taoist philosophers and the national hero Trần Hưng Đạo, the small temple was expanded in 1865.
From the shore the Welcoming Morning Sunlight Bridge (Cầu Thê Húc) leads to the island. Buildings of the temple include the Pen Tower (Thap But), the ink-slab (Dai Nghien), the Moon Contemplation Pavilion (Dac Nguyet) and the Pavilion against Waves (Đình Trấn Ba), all of which have symbolic meaning.
The temple is a popular spot for visitors to Hoan Kiem Lake.