Tāne Mahuta is a giant kauri tree (Agathis australis) in the Waipoua Forest of Northland Region, New Zealand. Its age is unknown but is estimated to be between 1,250 and 2,500 years old. It is the largest kauri known to stand today. Its Māori name means "Lord of the Forest" (see Tāne), from the name of a god in the Māori pantheon.

The tree is a remnant of the ancient subtropical rainforest that once grew on the North Auckland Peninsula. Other giant kauri are found nearby, notably Te Matua Ngahere. Tāne Mahuta is the most famous tree in New Zealand, along with Te Matua Ngahere. It is thought it was discovered (by Westerners, as it was already known to Maori) and identified in the 1920s when contractors surveyed the present State Highway 12 route through the forest. In 1928 Nicholas Yakas and other bushmen, who were building the road, also identified the tree.

According to the Maori creation myth, Tāne is the son of Ranginui the sky father and Papatuanuku the earth mother. Tāne separates his parents from their marital embrace until his father the sky is high above mother earth. Tāne then sets about clothing his mother with vegetation. The birds and the trees of the forest are regarded as Tāne’s children.