- Katarina was designed by Coronach.
- Katarina's bio has been revised by RiotRaven and Kitae in order to give her character more depth.
- Katarina is voiced by .
- Katarina's family name, Du Couteau, is derived from French, which means "Of the Knife".
- A framed portrait of Katarina can be seen in the preview video for the Mac Version Launch for League of Legends.
- Katarina is the sister of Cassiopeia, making them one of five pairs of sibling champions. The other siblings champions include Kayle and Morgana, Garen and Lux, Nasus and Renekton, and Darius and Draven.
- Katarina's Shunpo is possibly a reference to a fictional technique in the popular manga series . Its name is Japanese (written as 瞬步) and means "Flash Steps," indicating that the person can move between two spots in the blink of an eye.
- Katarina was one of the champions chosen for the Noxian pool available during the Ionia vs. Noxus match. However, she was not one of the selected champions.
- When Katarina was first released, her default skin was the one that is now labeled as her Mercenary skin. This also applied to her imagery on skill icons, which can still be viewed in-game. She later had her skin, her voiceovers, and her backstory reworked.
- Katarina's dance references from the last dance scene in the movie here.
. The scene can be seen
- It has since been changed; It still features the first part of the dance, but the later animation of the dance is now a punching motion with her knives that rapidly gains speed.
- Katarina is one of the few champions to feature two champion spotlights due to significant changes to her kit.
- Katarina's old voiceovers were similar to the new ones but were angrier. Her old voiceovers can be seen here.
- Katarina's old taunt used to be, "Remember, evil spelled backwards is live. No coincidence."
- Katarina's old joke is a reference to her old voice actor, who mispronounced the term "Dance Macabre". The joke refers to the , or "The Dance of Death," a medieval allegory on the "Universality of Death."
- Katarina is one of the few champions that had their in-game voices changed; others include Anivia, Janna and Nasus.
- Katarina's quote "Why? Because I can." is a tribute to Shawn Michaels, famous WWE wrestler.
- Bilgewater Katarina skin was inspired by ChiZ'sSwashbuckler Katarina skin.
- The Red Card Katarina skin, along with the soccer skins for other champions, appeared just before the 2010 World Cup started, and were removed from the store on October 31, 2010.
- Sandstorm Katarina has a new taunt animation in which she does a backflip instead of the usual animation.
- During the Maokai Art Spotlight, a photoshop tab called :File:Katarina OriginalSkin.jpg|katarina-painting1.jpg was visible. The image on the tab turned out to be a new splash art for Katarina's Classic skin.
- Katarina's Chinese artwork shows her having a tattoo on her right hip. This tattoo is also visable in the Season One trailer, but not on the normal splash art.
- Katarina in-game model now has a tattoo on her left side after the rework.
- Katarina currently has an unreleased skin under the name "Crimson Elite Katarina".
- Slay Belle Katarina's previous Recall Animation have her doing pole dancing with a candy cane (can be seen here) and was later changed to slicing a candy cane instead because Riot stated that the previous animation does not match with Katarina's theme.
- A man in Slay Belle Katarina's splash art is similar to Garen in clothing and hair. It might be done on purpose.
- Katarina and Garen first fought during a war between Demacia and Noxus.
- Katarina and Garen were the ones who stopped the inter-city brawl in Kalamanda.
- According to Blitzcrank's "Fleshling Compatibility Service," a dating service made by Blitzcrank, Katarina and Garen make a perfect couple, but are not officially together. Fans have since been joking about their relationship.
- Katarina once came to Demacia to protest about High Councilor Heywan Relivash's conspiracy in Kalamanda along with Jarvan IV. She was attacked but Garen defended her.
- With her unreleased skin, she is revealed to be part of the Crimson Elite, along with Riven and Talon.