This study As Buddhism was introduced into China in the two Han Dynasties, Han Chinese monks and Tibetan monks gradually translated Sanskrit Buddhist cannons into Chinese. They had discovered Gautama Buddha had prophesized the coming of the three periods of true dharma (saddharma), semblance dharma (saddharma-pratirupika) and dharma decline (saddharma-vipralopa). Mentions of the prophecies can be found in the Saṃyukta-āgama, which represents Early Buddhism, as well as texts related to the Mahayana branch of Buddhism. As history progressed, the end of the Han Dynasties led to the warring era of the Three Kingdoms. Chaos and suffering continued for more than two hundred years until the end of the Sixteen Kingdoms period. The lack of peace and prosperity reminded people of the dharma decline period in Buddhist texts , as a result, people started carving Buddhist texts, building Buddhist statues and erecting pagodas in search for blessings. The suppression of Buddhism by the Northern Wei Taiwu Emperor during the Sixteen Kingdoms period further worried the people Some of them became convinced that the dharma was facing extinction. The persecution of Buddhists under Taiwu’s reign became an extremely import element to the origin of the discourse of dharma decline school of thought. As the dharma decline school of thought increasingly took hold, new Buddhist branches centering on the end of dharma emerged. Founders of these branches aimed to warn the people with the dharma decline ideas in order to save the living beings in the world. This school of dharma decline thought also led to the discovery of significant documents and relics related to the idea of the dharma decline period. The popularity of the ideology of dharma decline in China leads one to question whether it existed in ancient India. However, the only way to answer this question is to look into the texts by ancient Indian Buddhist interpreters. Furthermore, the ancient Sanskrit texts that have survived in our times are relatively rare. Fortunately, there are many Chinese translation sutras and shastras, allowing scholars to approach the question using Tibetan translations instead of the Sanskrit originals. If the Han and Tibetan translations are not enough as proofs, Buddhist texts conversed in Tibet also include a large number of literature by ancient Indian Buddhist interpreters, from these texts treasures can be uncovered. Buton Rinchen Drub was a master of Buddhism, history and literature with historical status in Tibetan Buddhism. This study uses Buton’s work on the history of Tibet Buddhism as its basis and retraces to the works of the ancient Indian Buddhist interpreters in its research. Therefore, it can help to betterunderstand how the three periods are defined and differentiated in Tibetan Buddhism.