A master degree thesis conducted by Arjun Thapa in the supervision of Prof. Khadga Basnet was published by the Small Mammal Conservation and Research Foundation. The study examined diet composition, food niche breadth, and conservation threats of the Red Panda (Ailurus fulgens F. Cuvier 1825) in Langtang National Park of Nepal. The study was conducted in Gopache, Dhokachet, and Trishuli of the park, employed field survey, interview, and lab techniques. A total of 161 fecal samples and reference materials were collected from 12 line intercepts spaced by 150m at the elevations of 3000m-3600m for micro-histological analysis. Conservation threat data were generated through semi-structured questionnaire survey and interviews with local herders besides assessing the encounter rate of cattle dung and grazing intensity using the same intercepts. Data analysis showed that the red panda’s diet composed of eight different plant species including bamboo, tree, herbs, shrubs and moss. Bamboo (Thamnocalamus aristatus) ( =245.08±15.74%) contributed the most followed by Moss ( =5.91±1.95%), Sorbus cuspidata ( =5.83±1.22%), Juniper recurva ( =1.08±071.95%), Acer caudatum ( =1.00±0.38%), and other species like Rhododendron campanulatum, Abies spectabilis, and Rubus sp. in low proportions. All these plants except T. aristatus, which is consumed in all seasons (c2> 0.001, df =11, P>0.05), varied seasonally in composing the red panda’s diet. Food niche breadth determination showed a low value (0.000104), which suggested highly selective foraging habit of the species. Unident ified hairs, bones and claws were also observed in few fecal samples. Livestock grazing (e.g. Yak), firewood and fodder collection were the major threats of the red panda. Dhokachet site had the highest livestock grazing intensity as evidenced by the increased encounter rate of cattle dung with decreased fecal pellets of the red panda.