Buddhism appeared quite early in this area. Before the King Tran Thai Tong (1225 – 1258) followed Buddhism on Yen Tu mountain, many generations of true Buddhists had practised the religion there. The King Tran Nhan Tong (1279-1293) left home and became a monk on Yen Tu mountain where he founded the Truc Lam Zen Sect in Vietnam. In the 14th century, Yen Tu and Quynh Lam area (Dong Trieu) was the center of Buddhism Vietnam where gave training for monks nationwide. Many centuries later, Buddhism continued developing in Quang Ninh with hundreds of pagodas, of which there were some famous pagodas namely Loi Am pagoda, Long Tien pagoda (Hạ Long), Linh Khanh (Tra Co), Ho Thien (Dong Trieu), Linh Quang (Quan Lan) and so on.
After lots of historical changes and the destruction of nature and human beings, nowadays, there remain approximately 30 pagodas located in 8 districts, towns and cities. There is not an exact statistics of monks in Quang Ninh but it is easy to find that the number of people respecting Buddhism increases continuously. On the 1st and the 15th of each month according to the lunar calendar, people from everywhere visit pagodas and pray for good things.
The number of people respecting other religion is not as many as that of Buddhism followers. There are twenty-seven Christianity churches of nine regions belonged to forty-one parishes in eight districts, towns and cities. The number of Christianity people is about ten thousands ones. The number of Caodaiists (belong to Cao Dai religion) is under 100 people. The most popular belief in Quang Ninh is ancestor worship, worship of Tran dynasty heroes and worship of other deities./.