The lizard is about 35 to 50 cm long and is found in wet and dry sclerophyll forests, montane woodland and coastal heathlands. It is an omnivore with a diet consisting of leaves, flowers, fruit, slow-moving invertebrates, and small vertebrates. It has heavily lidded eyes that are well protected. The anus can excrete a foul-smelling musk. The tail can also be dropped (autotomy) when grasped by a predator (like most skinks) but these large skinks are much less likely to do so.
They are found in south-eastern parts of Australia including Tasmania and the islands of Bass Strait. In the northern parts of their range they are restricted to highland areas, whereas in southern Victoria and Tasmania they can be found right down to the coast. Some herpetologists believe that there are two distinct forms of this species - a highland or alpine form and a lowland or southern form. Specimens from the northern parts of the species range (alpine form) are generally larger and blacker. They also tend to have more colourful blotches on their back, sometimes being pale pink, salmon-pink or bright orange in colour.
Blotched blue-tongued lizards emerge from hibernation in late September (in Tasmania), mate in late October and the young are born in autumn (March-April). These large skinks are viviparous (give birth to live young) and long-lived (anecdotally 20 years or more). They have adapted well to some rural and urban areas where they can be found living on farms and in gardens, where they are an asset, as they love to eat pests like snails, slugs and occasionally rodents.
The blotched blue-tongued lizard is among the animals identified from the Pleistocene fossil sites of the Naracoorte Caves.
