Family name O'Riain (O'Riain 
) , around the world, is a rare cognomen. The family name O'Riain is characteristic of Ireland, where it is quite a rare surname, Australia, where it is a very rare surname, and France.
| VARIANT | COUNTRY |
|---|---|
| O'Riain | United Kingdom, Ireland, Australia, Canada, France |
| natasha selina o'riain (born 1963) (b. 1963) |
|
|
| paul o'riain Irish skipper, IE (b. 1968) |
|
|
| bearnard o'riain Peerage person ID=126467 |
|
|
| m justin o'riain researcher |
|