In this paper, R.A. Stein and Roerich are representatively introduced to examine King Gesar as they are the main researchers. In addition, throughout the investigation of King Gesar, it was examined how its spoken language was transformed into the wooden language. However, King Gesar is currently being presented on the stages nowadays, so it is not certain if its base story is genuine although it`s possible to catch some common elements from different editions. Tibetan Buddhism greatly influenced on King Gesar. On the Tibetan Buddhist aspect, Tibet has its own unique history. Not only they were influenced by Chinese Buddhism, but also were influenced by Indian Buddhism. As mentioned in the text, Padma-Sambhava, Atisa, Dromtonpa and Tsong-kha-pa who were all unique Buddhist thinkers appeared in the history. It can be expected to have more products as their long history of Buddhism still has many areas to explore. Upon looking into some possible areas to explore, this paper observed multiple chapters and the history of Tibetan Buddhism based on the study of King Gesar. Especially Padma-Sambhava`s book, `The Tibetan book of the dead` brought more attention to this research. This book in the humanity point of view can lead to more various ways of interpretation of Tibetan Buddhist heritage and is considered one of great legacies by Western scholars who are also highly interested in the psychological aspect of this book.