Prostanthera conniana is a species of flowering plant that is endemic to New South Wales.

It is an erect, open shrub with branchlets that are square in cross-section, narrow egg-shaped to narrow oblong leaves, and white flowers with bright yellow markings on the throat, the flowers arranged in groups of four to eight.

The flowers are arranged in groups of four to eight, the sepals green, sometimes with a maroon tinge.

[3][4] The specific epithet (conniana) honours Barry Conn and his wife Helen.

[3] This mint bush grows on steep rocky slopes in low, open scrub or woodland in four sites near the Shoalhaven River in Bungonia National Park.