Buddhism in Vietnam (Vietnamese: 'đạo Phật or Phật giáo') as practiced by the ethnic Vietnamese is mainly of the Mahayana tradition.Buddhism may have first come to Vietnam as early as the 3rd or 2nd century BCE from South Asia or from China in the 1st or 2nd century CE. Vietnamese Buddhism has had a symbiotic relationship with certain elements of Taoism, Chinese spirituality, and the Vietnamese folk religion.
There are conflicting theories regarding whether Buddhism first reached Vietnam during the 3rd or 2nd century BCE via delegations from India, or during the 1st or 2nd century from China. In either case, by the end of the second century CE, Vietnam had developed into a major regional Mahayana Buddhist center centering on Luy Lâu in modern Bắc Ninh Province, northeast of the present day capital city of Hanoi. Luy Lâu was the capital of the Han region of Jiaozhi and was a popular place visited by many Indian Buddhist missionary monks en route to China. The monks followed the maritime trade route from the Indian sub-continent to China used by Indian traders. A number of Mahayana sutras and the āgamas were translated into Classical Chinese there, including the Sutra of Forty-two Chapters and the Anapanasati.
Jiaozhi was the birthplace of Buddhist missionary Kang Senghui who was of Sogdian origin.
Over the next eighteen centuries, Vietnam and China shared many common features of cultural, philosophical and religious heritage. This was due to geographical proximity to one another and Vietnam being annexed twice by China. Vietnamese Buddhism is thus related to Chinese Buddhism in general, and to some extent reflects the formation of Chinese Buddhism after the Song dynasty.Theravada Buddhism, on the other hand, would become incorporated through the southern annexation of Khmer people and territories.