Last name Hyoil (효일 
, Hyoil 
) , worldwide, is a very rare family name. The last name Hyoil is characteristic of Eastern Asia, particularly China, where it is an extremely rare surname. Predominantly, Hyoil is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| 효일 | South Korea |
| Hyoil | South Korea, United States, China |