The Great Himalayan National Park (GHNP) is one of the World Heritage Sites in the Indian Himalayan Region. It supports representative,natural, unique, and socio-economically important biodiversity. Amongst the flowering plants, family Orchidaceae is unique and highly evolved. But the orchid species are facing tremendous pressure due to over exploitation, habitat degradation, and changing environmental conditions particularly climate change. Also, ecological status of these species is very poorly known. Therefore, the present study has been conducted to assess the orchid diversity of sub-alpine and alpine ecosystems of the Great Himalayan National Park. Rapid sampling and quadrat methods were used for the ecological assessment of the species. The economic importance of the species is based on the interviews of the local inhabitants. The intensive and extensive surveys resulted in the identification of 14 species representing 9 genera. These species were distributed between 2807-4025 m amsl and represented by the moist alpine, bouldary, riverine, rocky, and shady moist habitats. The species were also analyzed for their nativity, indigenous uses, and rarity. Amongst species, 12 species were natives and 02 species non-natives. Dactylorhiza hatagirea was recorded in maximum sites (12 sites), followed by Epipactis helleborine (11 sites), Calanthe tricarinata (04 sites), Calanthe plantaginea, Gymnadenia orchidis (03 sites, each), Epipactis royleana, Cypripedium cordigerum (02 sites, each) and Goodyera repens, Goodyera fusca, Epipactis gigantea, Malaxis muscifera, Platanthera edgeworthii, Goodyera biflora and Dienia cylindrostachya (01 site, each). Maximum orchids were found in shady moist habitat (21 spp.), followed by alpine moist (08 spp.), riverine and rocky (06 spp., each), and bouldary (02 spp.). The density of Epipactis helleborine ranged from 0.20-4.50 Ind m-2, Dactylorhiza hatagirea 0.03-3.58 Ind m-2, Epipactis royleana 1.90-3.58 Ind m-2, Calanthe plantaginea 0.60-0.90 Ind m-2, Gymnadenia orchidis 0.60-1.95 Ind m-2, Cypripedium cordigerum 0.15-0.60 Ind m-2, Goodyera fusca 0.30 Ind m-2, Epipactis gigantea 0.23 Ind m-2, Malaxis muscifera 0.10 Ind m-2, Platanthera edgeworthii 0.30 Ind m-2, Goodyera biflora 1.13 Ind m-2 , Dienia cylindrostachya 0.15 Ind m-2, and Goodyera repens 0.83 Ind m-2. Amongst the species, Calanthe plantaginea, Epipactis gigantea, Epipactis helleborine, Epipactis royleana, Goodyera fusca, and Platanthera edgeworthii were identified as Vulnerable.Calanthe tricarinata, Goodyera biflora, and Dienia cylindrostachya were identified as Near Threatened, Cypripedium cordigerum, Dactylorhiza hatagirea, and Gymnadenia orchidis as Endangered, Malaxis muscifera was identified as Critically Endengered and Goodyera repens was identified as Least Concern. Study on habitat ecology and periodical monitoring populations of these orchids has been suggested for understanding the dynamics and conservation status of their populations.