Nepal is one of the smallest countries in the world in its geographical area. It is the richest country in ethnic, socio-cultural, altitudinal, climatic, ecosystem and floristic diversity. The dominancy of an agrarian society of rural people is directly based on plant resources and have their own customary, traditional technology and knowledge concerning their cultural response to the plant world. The socio-cultural, economic and religious practices of the ethnic groups are in one way or other linked to the plants and plants products. So, in Nepal there is remarkable ethnic biodiversity and wealth of indigenous knowledge of plants with economic value. The interrelationship and interdependency between the human being and the plant world is closely associated with the emergence of human race, human culture and their successive evolution.