Eucalyptus lansdowneana, commonly known as the crimson mallee or the red-flowered mallee box is endemic to a restricted area of South Australia.

Eucalyptus lansdowneana is a mallee that typically grows to a height of 2–6 metres and forms a lignotuber.

Flowering mainly occurs between August and October and the flowers are crimson, ageing to pink.

Crimson mallee is restricted to the south western part of the Gawler Ranges where it grows in mallee vegetation on rocky outcrops and hilltops.