Surname Longyan (Longyan 
) , all around the world, is a very rare family name. The last name Longyan is habitual in Thailand, where it is a very rare surname, China, where it is an extremely rare surname, and the United States. More prevalently, Longyan is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Longyan | China, Nigeria, Taiwan, Thailand, India |