|Nickname:||Wild Man, Uncle Eugene|
|First appearance:||Say Uncle|
|Last appearance:||Say Uncle|
|Voice actor:||Dee Bradley Baker|
|Family:||Professor Utonium (1998 TV series) (brother)|
Bunny (deceased niece)
Eugene Utonium is the brother of Professor Utonium and the uncle of The Powerpuff Girls. He is introduced in "Say Uncle", when he sent a telegram to the Professor writing that he'll visit them for a day. The Professor shows the Girls a picture of himself and Eugene when they were both around their twenties.
- Aside from The Powerpuff Girls, who are technically his adoptive daughters, Eugene is the only known member of Professor Utonium's family, to appear or even be mentioned at any point in the entire series.
- He never met the Powerpuff Girls.