The Leichhardt River is a 603 km lon river in north-west Queensland, Australia.
The source of the river is in the Selwyn Range under Rifle Creek Hill and fed by Rifle Creek south of the mining town Mount Isa. It runs in a generally northerly direction almost parallel with the Diamantina Developmental Road until it reaches Mount Isa and crosses the Barkly Highway. It continues in a north easterly direction across the Gulf Country passing through Lake Moondarra past Glenroy Station then through Lake Julius. It then bears east then north again almost parallel with the Burke Developmental Road until crossing it near Nardoo. Continuing north past Augustus Downs Station to its mouth at the Gulf of Carpentaria.
The river was named by explorer and surveyor Augustus Charles Gregory after the early explorer of Australia, Ludwig Leichhardt.
The river is ephemeral and in the dry season the upstream reaches retract to a series of waterholes. The drainage basin and river estuary are in a near pristine condition.
The river is dammed near Mount Isa to form Lake Moondarra. Other storage facilities in the catchment include Julius Dam, East Leichhardt Dam and Rifle Creek Dam. Around 50 kilometres upstream from its mouth are the Leichhardt Falls.
