Because of its regional significance in terms of habitat and diversity of species, the Nam Ha National Protected Area (NPA) was designated as an ASEAN Heritage Site in 2003. Located entirely within Luang Namtha’s borders, the 222,400 square-hectare Nam Ha NPA covers 24% of the province and partly covers all five of the province’s administrative districts. It is the 4th largest NPA in Lao PDR and also the 4th largest protected area in the Northern Indochina subtropical forest zone. This zone has the highest species diversity for birds among all eco-regions in the Indo-Pacific Realm. Nam Ha is contiguous with the 77,500 hectare Nam Kan Provincial Protected Area in Bokeo and the 44,000 hectare Shiang Yong Protected Area in Yunnan, China. There is at least one group of elephants that regularly cross between Nam Ha’s upper Nam Kong watershed and Shiang Yong. The Nam Ha NPA harbors at least 38 species of large mammals and 22 endangered species have been observed in the area including the globally threatened clouded leopard and tiger.  There are small populations of Gaur, Asian elephant, and possibly a unique muntjac species living in and around the NPA. A survey in 2003 confirmed that the Black-cheeked Crested Gibbon, one of the rarest and endangered gibbon species, occurs in low numbers in at least three remote forest locations in Nale, Vieng Phoukha and Long districts.  The bird fauna is diverse with over 288 species found within the boundaries of the protected area. Key species include the Blyth’s Kingfisher, Grey-headed Lapwing, Pied Falconet, Green Cochoa, Yellow-vented Warbler, Rufous-throated Fulvetta and Short-tailed Parrotbill. The area contains nationally important populations of Silver Pheasant and has recorded the first recent sightings of the Crimson-breasted Woodpecker in Lao PDR.

The majority of the NPA lies at around 1000-1500 meters above sea level with an elevation range of 540-2094 m. The province’s largest mountain and one of the highest peaks in northern Lao PDR is within the western core zone of the NPA in Vieng Phoukha District. Climate here is moist to dry sub-tropical and the area receives about 1,500-2,000 mm of rain per annum. It is estimated that about 32% of the NPA is undisturbed or primary forest. Both the Nam Tha and Nam Kong rise in the northern Nam Kong core zone, part of an important catchment that provides water for Luang Namtha Town and villages living downstream.  Although lowland wet-rice cultivation is now the preferred method of rice production, evidence of swidden fields can be found among nearly all NPA land located within 5 kilometers of human settlement. Despite official efforts to reduce swidden cultivation, this method of agriculture is still commonly practiced.

In terms of NPA management zones, the protected area has been divided into 3 strictly protected core zones (Nam Kong, Phou Song Phan and the Central Core Zone) and multi-use areas where some livelihood activities like agriculture, hunting and the collection of non-timber forest products are permitted. Geographically, the NPA has four distinct areas: (i) The Luang Nam Tha Plain, made up of bamboo, secondary evergreen forests and scrub, (ii) the Northern Highlands Zone, with patches of primary evergreen forest mixed with secondary forest and large patches of imperata grass, (iii) the Southern Highlands, including evergreen forest and scrub, and (iv) the Nam Kong area along the border with China that has mainly secondary evergreen forest and scrub. The majority of undisturbed forest falls within the three core zones that cover 30% of the protected area, with the largest being the Central Core Zone situated west of Luang Namtha town extending to Vieng Phoukha and Sing District.  There are 104 villages that surround the NPA, all of which are reliant on the protected area for either a source of food, water, medicines, building materials or agricultural land.