Eucalyptus desmondensis, commonly known as Desmond mallee, is a eucalypt that is native to Western Australia.
The slender willowy mallee typically grows from a lignotuber to a height of 1 to 4.5 metres (3 to 15 ft) with smooth whitish bark. Adult leaves are disjunct, glossy, grey-green, thick and concolorous. The leaf blade are lanceolate or elliptic in shape and basally tapered. The supporting petioles are narrowly flattened or channelled. It blooms between August and June and produces simple axillary conflorescence with 11-flowered umbellasters with peduncles that are broadly flattened and yellow flowers. Fruits form later that are cylindrical or hemispherical or campanulate in shape.
It is found on sandplains and rocky hillsides in a small of the southern Goldfields-Esperance region of Western Australia centered around the Fitzgerald River National Park where it grows in stony clay, loam or sandy granitic based soils.
The species was first described in 1925 by the botanists Joseph Maiden and William Blakely in journal the Proceedings of the Royal Society of New South Wales from samples collected by Charles Austin Gardner from near Ravensthorpe in 1924.