Surname Onyinyechi (Onyinyechi 
) , around the world, is a common cognomen. The surname Onyinyechi is characteristic of Nigeria, where it is quite a common surname, Niger, where it is quite a rare surname, and the United States, where it is an extremely rare surname. Also, Onyinyechi is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Onyinyechi | Ireland, United Kingdom, United States, Niger, Nigeria |