Azalea State Natural Reserve, Nature reserve in Humboldt County, United States.

Azalea State Natural Reserve is a 30-acre (12 ha) reserve in McKinleyville, Humboldt County, California, just north of Arcata and above the Mad River. It protects the western azalea (Rhododendron occidentale), whose pink and white flowers bloom in April and May. A short self-guided nature trail focuses on north coast plants, and a picnic area is available.

The land was acquired in 1943 by the California Department of Parks and Recreation specifically to protect the native western azalea growing here and the surrounding habitat. It is one of the earlier examples of California setting aside land to safeguard a native plant community rather than a landscape feature.

The western azalea growing here is a native shrub that belongs to the coastal redwood forest, not a garden variety. Visitors who come in spring can see it flowering among the conifers and ferns in its natural setting.

The reserve sits just off the road north of Arcata and is easy to find with basic signage along the way. The walking trail is short and mostly flat, so most visitors can cover the whole area without difficulty.

The reserve covers 30 acres (12 ha) and was acquired by the state in 1943. Its self-guided nature trail focuses on north coast plants, among them conifers of the redwood forests, Iris and Lilium occidentale, a lily native to northern California and Oregon. The site lies at 40°55′6″N 124°04′48″W, with annual rainfall averaging about 1,300 mm.