It is stockily built, with large paws, strongly curved claws, small, rounded ears and a short snout.

Being omnivores, sun bears' diet includes ants, bees, beetles, honey, termites, and plant material such as seeds and several kinds of fruits; vertebrates such as birds and deer are also eaten occasionally.

These bears are threatened by heavy deforestation and illegal hunting for food and the wildlife trade; they are also harmed in conflicts with humans when they enter farmlands, plantations, and orchards.

The generic name Helarctos comes from two Greek words: ήλιος (hēlios, related to the sun) and αρκτος (arctos, bear).

[10] H. annamiticus, described by Pierre Marie Heude in 1901 from Annam, is not considered a distinct species, but is subordinated as a junior synonym to H. m.

[4][8][31] It is stockily built, with large paws, strongly curved claws, small rounded ears and a short snout.

[4][32] The characteristic chest patch, typically U-shaped, but sometimes circular or spotlike, varies from orange or ochre-yellow to buff or cream, or even white.

[32][37] The teeth are very large, especially the canines, and the bite force quotient is high relative to its body size for reasons not well understood; a possible explanation could be its frequent opening of tropical hardwood trees with its powerful jaws and claws in pursuit of insects, larvae, or honey.

[30][31] The overall unique morphology of this bear, such as its inward-turned front feet, flattened chest, and powerful fore limbs with large claws, indicates adaptations for extensive climbing.

[44] A study published in 2019 described skillful mimicry of facial expressions by sun bears, with precision comparable to that seen in gorillas and humans.

[8][44] Sun bears stand on their hind feet for a broader view of their surroundings or smell far-off objects; they try to intimidate their enemies by displaying their chest patch if threatened.

[4][8] Vocalisations include grunts and snuffles while foraging for insects, and roars similar to those of a male orangutan during the breeding season; less commonly, they may give out short barks (like a rhinoceros) when they are surprised.

[43] Tigers are their major predators; dholes and leopards have also been recorded preying on sun bears, but cases are relatively few.

[49] In another incident, a wild female sun bear was swallowed by a large reticulated python in East Kalimantan.

[50] Sun bears are omnivores and feed on a broad variety of items, such as ants, bees, beetles, honey, termites, and plant material such as seeds and several kinds of fruits.

Sun bears tear open hollow trees with their long, sharp claws and teeth in search of wild bees and honey.

[55] A study in Central Borneo revealed that sun bears play an important role in the seed dispersal of Canarium pilosum (a tree in the family Burseraceae).

They occur in montane areas in northeast India, but may not extend farther north into the unfavourable and colder Himalayan region; their distribution might be restricted to the northwest due to competition with sloth bears.

[2][4] The sun bear tends to avoid heavily logged forests and areas close to human settlement.

[65][66] A survey in Lower Kinabatangan Segama Wetlands showed that sun bears were feared but were not common in oil palm plantations; Bornean bearded pigs, elephants and macaques were far more damaging to crops.

Fossils also known from the Middle Pleistocene of Thailand along with Stegodon, gaur, wild water buffalo, and other living and extinct mammals.

Sun bear populations appear to decrease in size northward from Sundaland, and numbers are especially low in the northern and western extremes of the range.

[2][31] Compared to other continents, Southeast Asia has undergone severe depletion in forest cover over the past few decades (by almost 12% between 1990 and 2010); this has resulted in substantial habitat loss for forest-dependent species such as sun bears.

[70][71] A 2007 study in East Borneo recorded severe loss of habitat and food resources due to droughts and forest fires brought about by the El Niño.

In Southeast Asia, a male leopard (Panthera pardus) has been photographed with a sun bear cub being held by the throat.

Studies have found evidence of pet trade and sale of sun bear parts such as gall bladders in traditional Chinese medicine (TCM) shops in Sabah and Sarawak.

[76] Sun bears were killed by shooting or administering poison to protect coconut and snakefruit plantations in east Kalimantan.

[80] Protective laws have shown little success in controlling these threats, especially due to poor execution and high potential for gains by the trade.

[83] The Malayan sun bears are part of an international captive-breeding program and a species survival plan under the Association of Zoos and Aquariums since late 1994.