Powers, Skills, and Abilities,
- Gifted Intellect:
- Trained Pyschiatrist:
- Expert Combatant:
- Master Acrobat: Harley's skills in gymnastics rival with those of Catwoman and Nightwing.
- Enhanced Strength & Stamina: Harley's strength and stamina has been augmented by injections given to her by Poison Ivy.
- Toxic Immunity: Immunizes her to various assorted toxins and Ivy's own poisonous
- Psychiatry: Trained as in the field of psychoanalysis.
- Gymnastics: She is a very spectacular gymnast. Her skills rival with those of Catwoman and Nightwing.
- Acrobatics: She's been able to twist and turn out of some pretty tight situations.
- Gadgetry: Harley knows there's clown inside everyone just waiting for the opportunity to put on a big red nose, floppy shoes and burst out.
- Leadership: After Joker's passing, his gang did not split up thanks to Quinn. Harley Quinn leads the entire gang herself, but they did not trust her as much as much as they did the Joker.
- Indomitable Will
- Genius Level Intellect
- Singing: Harley is a surprisingly talented singer.
- Martial Arts
- Medical Science
- Tactical Analysis
- Hand-to-Hand Combat (Basic/Advanced): She has also been shown to have some ability in hand to hand combat; being able to hold her own against Helena.
- Manipulation: Harleen Quinzel is very manipulative. She is able to convince people to do anything and is extremely violent. This means she will resort to any means necessary so crossing her is not something people normally do.
- Mental Illness: Joker managed to single handedly break Quinzel's sanity, leading her to take on the persona of Harley Quinn.
- Mental Instability
- Pie Bomb
- Baseball Bat: Harley carries a baseball bat with the superscription "Good Night"
- Giant Gag Mallet
- Pop Pistol
- Missile-Firing Pistol
- Rubber Chicken
- Dual Snub-Nosed Revolvers
- Dual Snub-Nosed Pistols
- Heart-Shaped Grenades
Friends and Allies
- The Joker- Love Interest
- Poison Ivy- Best Friend