Cognomen Sungja (Sungja 
) , worldwide, is a rare last name. The surname Sungja is characteristic of Eastern Asia, particularly South Korea, where it is a rare surname, and China, where it is an extremely rare surname. Also, Sungja is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Sungja | China, South Korea, United States, Canada, France |