A Biography of Monks Who Went Overseas for Dharma in Tang Dynasty is one of the works of Master Yi Jing in Tang dynasty, it was accomplished in 691. The book records stories of 61 monks who went to states in south sea, ancient Sri Lanka and ancient India for better understanding of Dharma though different routes, 38 of which started sailing from Guangzhou, Hepu, Wulei, Jiaozhi, Aizhou, Bijing and Zhanbo. This article summarizes monks and their different routes based on the records in the book, analyzes the factors why the routes of foreign cultural communication changed in early Tang dynasty. These monks made a contribution to cultural exchanges between Tang and foreign countries.