Halocarpus kirkii is a dioecious lowland forest tree endemic to New Zealand.

It is not a common tree, sometimes being found in lowland forests to an altitude of 700 metres in the north of the North Island from Te Paki (Radar and Unuwhao Bush) south to near Limestone Downs (south of Port Waikato) in the west and about the southern Kauaeranga Valley in the East including the Coromandel Peninsula and Great Barrier Island. Halocarpus kirkii ultimately reaches a height of about 25 metres, with a trunk up to 1 metre thick. Lower branches are spreading while the upper ones are erect. It has grey-brown bark which is smooth on young trees but on old trees, it has rough and pustular texture. It can be usually distinguished by its juvenile foliage, which often remains on the lower branches until the tree grows to approximately 10 metres tall. The leaves of the younger trees and on the lower branches of the adults are narrow and to some extent leathery, up to 4 cm long and 3 mm wide. The adult leaves are thick, scale-like and much smaller; the leaves overlap and lie appressed to the branchlets in 4 rows.