| Bridge Name: | Bai Chay Bridge |
| Native Name: | Cầu Bãi Cháy |
| Carries: | 4 lanes (cable-stayed section) and 6 lanes (other sections), 2 lanes each way and 2 pedestrian lanes |
| Crosses: | Hạ Long Bay |
| Locale: | Quảng Ninh Province, |
| Design: | Cable-stayed bridge |
| Height: | 150m (490feet) |
| Mainspan: | 435m (1,427feet) |
| Length: | 1106m (3,629feet) |
| Width: | 25m (82feet) |
| Below: | 50m (160feet) |
| Maint: | Ministry of Transport of Vietnam |
| Builder: | Shimizu Sumitomo Mitsui Construction |
| Begin: | May 18, 2003 |
| Open: | December 2, 2006 |
The Bãi Cháy Bridge (Vietnamese: Cầu Bãi Cháy|links=no) is a cable-stayed bridge on Highway 18, connecting Hồng Gai with Bãi Cháy over the Cửa Lục straits, separating Cửa Lục Bay with Hạ Long Bay, on the territory of Hạ Long city, Quảng Ninh province, Vietnam. It is the first, and at the time of its inauguration, the longest central-line cable-stayed bridge in Vietnam.
The bridge has two outer span of reinforced pre-stressed concrete box beams, which are the widest of the world for this type of bridge. The towers are located on a huge pneumatic caisson foundation system, a modern construction technology first applied in Vietnam on this project. The bridge was constructed using a balanced cantilever technology, wherein the bridge beams reaching out over the water and the aligned ends connect at a head height of 50m (160feet) above the water level. This technique assured that vessels could still operate normally during the construction process.
The bridge was completed and opened for traffic on December 2, 2006. The bridge was built to address the needs of the local people and tourists, and also to complete the discontinuation of the Bãi Cháy ferry line.