The Great Dividing Range, also known as the East Australian Cordillera or the Eastern Highlands, is a cordillera system in eastern Australia consisting of an expansive collection of mountain ranges, plateaus and rolling hills. It runs roughly parallel to the east coast of Australia and forms the fifth-longest land-based mountain chain in the world, and the longest entirely within a single country. It is mainland Australia's most substantial topographic feature and serves as the definitive watershed for the river systems in eastern Australia, hence the name.

A cordillera is an extensive chain and/or network system of mountain ranges, such as those in the west coast of the Americas. The term is borrowed from Spanish, where the word comes from cordilla, a diminutive of cuerda ('rope').