It is the smallest member of the genus Zaglossus, being closer in size to the Short-beaked Echidna. The male is larger than the female, and is further differentiated from females by the spurs on its hind legs. It weighs from 5 to 10 kilograms (11 to 22 lb).

The Long-beaked Rchidna is solitary, meeting with its own kind only once a year to mate. During the reproduction stage, the female lays the eggs after about eight days, with the offspring staying in their mother’s pouch for around eight weeks or until their spines develop. It is nocturnal; it rolls up into a spiny ball when it feels threatened like hedgehogs. Its diet consists of earthworms, termites, insect larvae, and ants, which it eats in the evenings by probing soft soil and leaf litter with its long nose, leaving tell-tale deep conical imprints called nose pokes.

The Long-beaked Echidna exists in a single location that is less than 20 km² on a single mountain in the Cyclops Mountains in Papua Province, Indonesia.

The main anthropogenic threats to the Long-beaked Echidna are habitat loss and hunting.  It was thought to be extinct until some of its “nose pokes” were found in the mountains of New Guinea during an expedition in 2007. Hunting by local people in the Cyclops Range continues to be a major threat. The habitat for this species is also being degraded by logging and by expansion of small-scale agriculture.