Agonis undulata is a species of flowering plant in the family Myrtaceae, and is endemic to the Fitzgerald River National Park in the south of Western Australia.

It is an erect shrub with more or less sessile, egg-shaped leaves with the narrower end towards the base, white flowers, and broadly cup-shaped capsules.

Agonis undulata is an erect sbrub that typically grows to a height of up to 2 m (6 ft 7 in), mature plants with thick, gnarled branches.

Flowering has been recorded in September and March, and the fruit is a hairy, broadly cup-shaped to top-shaped capsule 4–5 mm (0.16–0.20 in) in diameter.

[6] This species of Agonis grows in shrubland or heath and is has only recorded from the Fitzgerald River National Park near the coast of southern Western Australia.