Family name Oijennus (Oijennus 
) , across the world, is a rare last name. The cognomen Oijennus is habitual in Northern Europe, particularly Finland, where it is quite a rare surname.
| VARIANT | COUNTRY |
|---|---|
| Oijennus | Finland |
| oiva oijennus Finnish ice hockey player, FI (b. 1953) |
|
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| markus oijennus Finnish ice hockey player, FI (b. 1970) |
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