The topic of my thesis is the klu as perceived in Tibetan worldview and as the object of cult. The klu is one of the most emblematic classes of supernatural forces in the world of deities and spirits in Tibet, and their influence on the social-religious life of the Tibetans is significant. They are believed to embody such natural resources and territories as forests, springs, fountains, lakes, oceans, hills, mountains, and even solitary old trees. Particular focus is put on the historical background of the klu as portrayed in textual sources, actual concepts and practices connected with the klu as they appear in the area of study. Specific attention is given to the problems of classifying the klu in Tibetan cosmology and the ambivalence connected with this class of beings. Further, this study also discusses how beliefs and practices of the klu are evident not only in texts, religious rituals and but also in everyday activities. As the main themes of this research, I intend to delineate the role of the klu in the Tibetan cultural area primarily based on religious texts as well as local perceptions, supplemented by individual accounts and practices in Kyagya (sKya rgya) , a Tibetan village in Jantsa (gCan tsha) Tibetan autonomous County in Amdo (A mdo), and in the Tibetan communities nearby. This study, is divided into five sections on the basis of the following themes: an introduction to the study being chapter one, a general background to the study being chapter two, the virtuous klu and the non-virtuous aspects of the klu being chapter three, ritual practices being chapter four, and a concluding chapter. The first chapter presents a general introduction to the study by presenting a general overview of the cult of the klu in Tibet, the importance of this current research, research history, materials and methodology used in this study, experiences and outcomes from fieldwork research, bias and reliability of the material and ends with an outline of this study. The second chapter centers on the general background to the klu cult providing some insights into its characteristics as described in the Tibetan literary tradition. This chapter first provides a general sketch of the Indian background of the klu followed by sections reflecting on its Tibetan background, typological considerations, cosmological classification, and caste division presenting different viewpoints on how it originated, and how it survived and adapted to the ever-changing socio-religious life of the Tibetan people. The third chapter discusses the klu in two categories: one is the klu on the side of virtue, supported by their divine characteristics and positive aspects in the Tibetan cultural context. The other type is the klu on the side of non-virtuous and demonic, supported by presenting the negative aspects of the klu, such as their destructive aspects connected with disease, as well as environmental and weather-related disasters. The fourth chapter focuses on topics surrounding ritual practices concerning the klu and provides descriptions of relevant texts.