Nightcap National Park, Nature reserve in Northern Rivers, Australia.

Nightcap National Park is a protected forest reserve in Northern Rivers that covers steep mountain terrain with dense rainforest, cascading waterfalls, and narrow gorges. The land rises to mountain peaks around 930 meters and stays wet and misty most of the year due to heavy rainfall.

The park was created in April 1983 under the Forestry Revocation and National Park Reservation Act, covering part of Goonimbar State Forest; the rest of Goonimbar and part of Whian Whian State Forest were added later that year. Its establishment followed the Terania Creek blockades of 1979, the first rainforest anti-logging protests in Australia, and the three-year Rainforest War. Campaigning and blockading in 1998 led to further Whian Whian State Forest sections being added.

The park lies within the country of the Bundjalung nation, and several groups lived in the Nightcap Range, among them the Wiyabal, Nganduwal, Galibal and Githabul-speaking peoples. The Wiyabal occupied the range for at least 4000 years. Rock shelters in the park served as living places, and the landscapes, plants and animals appear in dreaming stories; sacred sites remain in the area.

The park is reached by four unsealed roads that can become slippery after rain, so check conditions before driving in. Picnic areas sit at Minyon Falls lookout, Minyon Grass, and Terania Creek, and many places require walking on hiking trails to reach them.

The Nightcap oak (Eidothea hardeniana) was only scientifically described in 2000 and is known from a single site in the park, with about 100 mature plants. The park records the highest annual rainfall in New South Wales, and 430.5 mm fell there in a single day.