Professor Utonium is the "father" and creator of the Powerpuff Girls. He is known for his gentle ways and being much caring for his children. He is also an inventor and a scientist and has a huge merit of inventions in his backpack. His interactions with the girls often include what one would think of as common events in a household with 3 children, such as telling them to eat their broccoli in the episode Beat Your Greens.
When he was child he was a terrible brat who had no interest in education however he was rescued by "three perfect girls'' from the future from Mojo Jojo, Utonium then become obsessed with science creating the Powerpuff Girls.
Even though he is very overprotective of Blossom, Buttercup and Bubbles, he is a very supportive, loving and affectionate father. Who helps the girls with his pep talks which brings the girls out of their sadness or anger. However he can be quite firm on the girls if he needs to be such as if the girls are falling asleep in school in the episode Daylight Savings.
His most successful inventions were made by accident such as The Powerpuff Girls themselves or a containment device however most inventions he creates on purpose either fail or have one major flaw. This also includes his cooking skills such as how one year the chili he made for the Townsville cook-off caused a hazmat crew to border off the house.
He lies to make the girls believe he is a responsible and mature adult however this has backfired multiple times such as how he lied to the girls saying he had a lot of work to do when really he had enough spare time to watch a sports game.
Professor Utonium is also very unlucky in love if his relationship with Sedusa, Ms. Bellum and Ms. Keane are any indication such as Sedusa wormed her way into the family circle to prevent the girls from stopping her crime sprees. Ms. Keane didn't understand why he disliked cats so much while he was would-be husband for Ms. Bellum.
- Utonium's voice actor Tom Kane also voiced Commissioner Gordon in LEGO DC Super-Villains and Admiral Ackbar in the Star Wars franchise in addition to voicing Gandalf in LEGO Dimensions.