The Australian green tree frog is larger than most Australian frogs, reaching 10 centimetres (4 inches) in length. The average lifespan of the frog in captivity, about sixteen years, is long in comparison with most frogs. Green tree frogs are docile and well suited to living near human dwellings. They are often found on windows or inside houses, eating insects drawn by the light. The green tree frog screams when it's in danger to scare off its foe; and this particular frog squeaks when it is touched.

Due to its physical and behavioural traits, the green tree frog has become one of the most recognisable frogs in its region, and is a popular exotic pet throughout the world. The skin secretions of the frog have antibacterial and antiviral properties that may prove useful in pharmaceutical preparations.

Its colour depends on the temperature and colour of the environment, ranging from brown to green; the ventral surface is white. The frog occasionally has small, white, irregularly shaped spots on its back. At the end of its toes, it has large discs, which provide grip while climbing. The eyes are golden and have horizontal irises,and the fingers are about one-third webbed, and the toes nearly three-quarters webbed. The tympanum (a skin membrane similar to an eardrum) is visible.

The green tree frog appears similar to the magnificent tree frog (Litoria splendida), which inhabits only north-western Australia and can be distinguished by the presence of large parotoids and rostral glands on the head.

The green tree frog is native to northern and eastern regions of Australia and to southern New Guinea. Distribution is limited mostly to areas with a warm, wet tropical climate. In New Guinea, the green tree frog is restricted to the drier, southern region. Its range spans from Irian Jaya to Port Moresby, and is most abundant on Daru Island. There have been isolated records in northern New Guinea, however this is thought to have been through introduction by humans.

The species has been introduced to both the United States and New Zealand. In the United States, it is restricted to two regions within Florida, where it was possibly introduced through the pet trade. Only small populations have been found in Florida, and it is unknown whether they have caused any ecological damage as an invasive species. In New Zealand, a population was once present; however, there have been no sightings since the 1950s.

They are nocturnal and come out in early evenings to call (in spring and summer) and hunt for food. During the day they find cool, dark, and moist areas to sleep such as tree holes or rock crevices. In the winter, green tree frogs do not call and are not usually seen.

Depending on their location, green tree frogs occupy various habitats. Typically, they are found in the canopy of trees near a still-water source. However, they can survive in swamps (among the reeds) or in grasslands in cooler climates. Green tree frogs are well known for inhabiting water sources inside houses, such as sinks or toilets. They can also be found on windows eating insects. They will occupy tanks, downpipes, and gutters, as these have a high humidity and are usually cooler than the external environment. The frogs are drawn to downpipes and tanks during mating season, as the fixtures amplify their call.