Family name Gwein (Gwein 
) , throughout the world, is a very rare cognomen. The cognomen Gwein is characteristic of Myanmar, where it is a rare surname, Germany, where it is a very rare surname, and the United States, where it is an extremely rare surname. Much less frequently, Gwein is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Gwein | United States, Philippines, Myanmar, Germany |