The species were reported in peat swamp forests at Pru Toa Daeng, Thailand (Kanchanasaka et al. 1998), and U Minh Thuong and Ha National Parks in Viet Nam (Nguyen et al. 2001). In Viet Nam, the species has recovered after the Viet Nam War.  Road killed otters were also found near peat swamp forests in southern Sumatra, Indonesia (Lubis 2005), at Tumpat in Kelantan, Pekan and Muazam in Pahang, (Abdul-Patah et al. 2020) between Sungei Besar and Tanjung Malim, Selangor, Malaysia (Tan 2015). Peat swamp forests are assumed to be one of the most important habitats for this species.

In seasonally flooded forests of the Tonle Sap Lake, the species expands its range to the interiors of the Lake’s forested area at high water level, and shrinks to the shore at low water level (Heng 2007, Willcox et al. 2016.)

Tropical forests were also their habitat, at Taman Negara in Pahang (Baker 2013), at Ulu Muda forest reserve in Keda in 2016 (Salahshour 2016) in Malaysia, and Hala Bala in Thailand (Sasaki pers.comm.).

The species was reported at low land wetland including Melaleuca and disturbed secondary forests, at Thale Noi in Phattalung, at Bor Lor in Nakhon Sri Thammarat, Thailand (Wanlop pers. comm.), at Bassac Marsh along the Mekong River, Cambodia (Heng et al. 2016).  It inhabits along coastal areas near mangroves in Southern Sumatra, in Indonesia (Latifiana and Pickles 2013), Peam Krasop wildlife sanctuary, Dong Peng Multiple Use Area, Ream National park, Cambodia (Heng et al. 2016), Deramakot Forest Reserve (Wilting et al. 2010), near Tabin Wildlife Reserve (Ishigami et al. 2017), Selangor in Malaysia (Woo. pers. comm.) and Danum Valley Conservation Area (Tantipisanuh et al. unpublished) in Sabah, Malaysia.

Road killed otters were reported in oil palm plantations, at Potian in Johor, Tasek Bera and near Chenor in Pahang, Malaysia, near Dungun in Terengganu, near abandoned mining ponds at Gopeng in Perak and Paya Indah, in Selangor (Abdul-Patah et al. 2020, Sasaki pers. comm.). The species was found near oil palm and mangrove in Southern Central Kalimantan (Huda et al. 2019).

At altitude, about 900 m and in mountains, two skins from the northern Myanmar were reported (Sasaki et al. 2009, Duckworth and Hills 2008, Shepherd and Nijman 2014).  At Cardamom Mt. in Cambodia, the species were found (Long 2000, Heng et al. 2016). Though Wayre (1974, 1978) considered that the species mainly inhabited above 300 m, mountain areas are not considered as the main, but subsidiary habitats

Heng et al. (2016) reported that the species is cathemeral, although showing trends toward more crepuscular or nocturnal behaviour in Cambodia.

The Hairy-nosed Otter is the rarest and least known among the five species of otters occurring in Asia. It is endemic to Southeast Asia. The type specimen came from Sumatra. Once believed to be extinct, the Hairy-nosed Otter has been rediscovered in many parts of Southeast Asia. In southern Thailand it has been reported from Pru Toa Daeng Peat Swamp Forest, Narathiwat (Kanchanasaka 2000), Hala Bala Wildlife sanctuary, Narathiwat (Sasaki pers.comm.), Thale Noi, Phattalung and Bor Lor, Nakhon Sri Thammarat (Tantipisanuh et al. unpublished). In Viet Nam it has also been reported from U Minh Thuong Nature Reserve (Nguyen et al. 2001) and U Minh Ha National Park in Mekong Delta and from Cambodia it has been reported from Tonle Sap wetlands, Bassac Marsh along the Mekong River, Cardamom Mt. and three areas along coast, Peam Krasop wildlife sanctuary, Donf Peng Mutiple Use Area and Ream National park (Heng et al. 2016, Willcox et al. 2016). It has been reported from Malaysia at Keda (Salahshour 2016), Pahang (Baker 2013), Selangor (Tan 2015) and Trengganu (Sasaki et al. 2009) and at Kelantan, Perak, Johor in 2010, Sabah (Abdul-Patah et al. 2020). In Sabah, Malaysia, this species was confirmed at three areas, viz. Deramakot Forest Reserve (Wilting et al. 2010), Tabin Wildlife Reserve (Ishigami et al. 2017) and Danum Valley Conservation Area (Wai pers.comm.).   In Brunei, a road killed otter was confirmed in 1997 (Sasaki et al. 2009). It has been recently reported in Southern Sumatra, (Lubis 2005, Latifiana and Pickles 2013) and in Southern Central Kalimantan (Huda et al. 2019), East and South Kalimantan (Reza pers. comm.) in Indonesia. In Myanmar, one old skin from the northern mountain area was kept in British Museum of Natural History (Sasaki et al. 2009, Duckworth and Hills 2008) and a skin of a Hairy-nosed Otter were confirmed at a market in Mong La, Shan State (Shepherd and Nijman 2014). The hairy-nosed otter ranges from Myanmar, Thailand, Cambodia, Viet Nam, Malaysia, Brunei and Indonesia. It is thought to occur in Lao PDR.

Lutra sumatrana is listed on Appendix II of the CITES. It is legally protected in all the range countries. In Thailand all otter species have been protected since 1961 under the Wild Animals Preservation and Protection Act and are listed as endangered species in the Thailand Red Data Book (Nabhitabhata and Chanard 2005). In Viet Nam, otters are protected and their hunting and use is strictly banned under the Government Decree 32/2006. In Cambodia, the Hairy-nosed Otter is listed as Rare and is considered fully protected under the Law on Forestry 2002. In Malaysia, different levels of protection are accorded to otters. The Hairy-nosed Otter is protected in Peninsular Malaysia under the Wildlife Conservation Act 2010. In Sabah, the Hairy-nosed Otter is protected under the Wildlife Conservation Enactment 1997. In Sarawak all otter species are listed as protected animals under the First Schedule [Section 2(1)] PART II] of the Wild Life Protection Ordinance, 1998. In Indonesia, the Hairy-nosed Otter is protected under Law Number 7, 1999. It is not protected under Myanmar’s Protection of Wildlife and Wild plants and Conservation of Natural Areas Law because the species was not recognized as occurring in Myanmar (Than Zaw et al. 2008).

A Global Otter Conservation Strategy covering of all the 13 species of otters has been prepared (Duplaix and Savage 2018) which inter-alia discusses the population trend, threats, and conservation actions required for the long-term survival of the species.