Nepal is a small country (147,181㎢) located in a borderline between two bio-geographical regions, Palearctic in the north and Oriental in the south. It has wide altitudinal variation from flat plain to high Himalaya (60-8848m). Due to the unique climatic and geographical variations, it is rich in biodiversity. Altogether 211 species of mammals, 878 species of birds, 182 species of herpeto-fauna and 232 species of fishes have been recorded in Nepal. Mammalian species occupied the 4.2% species of all mammals of the world. All together 46 species of mammals are listed under the categories of threatened IUCN threatened category including one regionally extinct, eight critically endangered and 25 endangered species. Small mammals have significant part (71.6%) in total mammalian species of Nepal. It occupies 151 species under seven orders and 25 families. Two species of small mammals Himalayan Field Mouse (Apedoemus gurkha) and Mouse-eared Myotis (Myotis csorbai) are endemic to Nepal. Among the small mammals (for example, rodents) occupied the highest number (52 spp.) and Chiroptera occupies the second position (51 spp.). Field-collection and observation of small mammals has been done three times since December, 2014 to February, 2016 in three different locations Kathmandu (1,200-1,800m), Pokhara (827-2,600m) and Lumbini (65-2,000m) of Nepal. Live-traps (Sherman trap) and traditional mouse-catching live-traps in different size were used to collect small mammals. A total of 221 individuals were captured from different habitats, human settlement (129 individuals), grassland (46 individuals), forest (25 individuals) and agriculture land (21 individuals). 99 individuals were collected from Lumbini following by 83 individuals from Pokhara and 39 individuals from Kathmandu. Morphological measurement has done in each species and their biological samples were collected. Altogether, four orders, four families and 19 species of small mammals were collected and identified. In addition, three species of monkey (Macaca assamensis, Macaca mulata and Semnopithecus schistaceus) and one species of flying fox (Pteropus giganteus) were observed in their natural habitats. A total of eleven taxa of Muridae family (Bandicota bengalensis, Canomys Badius, Mus booduga, Mus musculus, Niviventer fulvescen, Rattus nitidus, Rattus norvegicus, Rattus pyctoris, Rattus rattus, Rattus tanezumi, and Tatera indica) were identified within species level but three taxa were identified within genus level (Mus spp., Niviventer spp. and Rattus spp.). Among the collections, Rattus rattus was most dominant (33.93%) and Suncus murinus (20.81%) as well as Mus musculus (12.21%) occupied second and third position, respectively. Rattus rattus, Rattus tanezumi, Rattus norvegicus and Suncus murinus were abundant in all habitats but Rattus pyctoris, Canomys badius and Tatera indica only found in wild habitats, grassland and forest. In this study Canomys badius, Niviventer fulvescen, Tatera indica and Semnopithecus schistaceus are truly wild species but remaining 19 species are urban species. This study shows that large numbers of small mammals are urban type and their habitat is associated with human beings. For more clear understanding the ecological roles of Nepalese small mammals found, further continious monitoring and comprehensive studies are required to obtain abundant information applicable to comparative analyses of intraand inter-species interaction in the wild and urban habitats of Nepal.