Family name Ketko (Ketko 
, Кетько 
, Кетко 
) , worldwide, is a rare surname. The family name Ketko is habitual in Belarus, where it is quite a rare surname, Slovakia, where it is a rare surname, and Finland. Measured by absolute frequency, it is commonest in Belarus, Russia, and Thailand. Very seldom, Ketko is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Ketko | Finland, United States, India, Canada, Slovakia |
| Кетько | Russia, Ukraine, Belarus |
| Кетко | Kazakhstan, Russia, Kyrgyzstan, Belarus, Ukraine |
| เกตุกอ | Thailand |