She is responsible for raising and setting the moon in Equestria. In daily life, she is highly impulsive and easily agitated, possessing an excellent ability to manipulate the psychology of others. Her aura often strikes fear into other ponies. Perhaps because she was sealed away for so long, or because she sleeps during the day and works alone at night, she does not care much for the feelings of others. Unlike Celestia, who is always smiling, Luna often wears a blank expression or a frown. She harbors feelings of inferiority and jealousy toward her older sister, Celestia. Consequently, she is said to be deeply obsessed with her. She speaks informally to everyone.

She is responsible for regulating the love and desires of ponies. She is extremely warm and kind. Despite being a princess, she is not authoritarian and is highly considerate of others. She values 'relationships' and 'bonds' over raw emotion. She remains calm and devoted even in crises, but can become cold and blunt in grave or dangerous situations. She generally maintains a gentle atmosphere. She is said to have high empathy. She uses polite language with all the other queens except for Twilight Sparkle.

She is responsible for regulating the friendships and relationships of ponies. She maintains smooth and broad social relationships even with ponies outside her circle of friends. Her personality is generally very diligent and rational, and she tries to act accordingly. She is well-spoken and knowledgeable, often playing the role of mediator, negotiator, and coordinator when conflicts arise. While she appears very rational and calm, she is actually a severe paranoid perfectionist. She has a tendency to become easily frustrated by small failures, which often leads to mental breakdowns. She never lets even a minor mistake slide; when this trait manifests intensely, she loses her usual calm and rational demeanor, either exploding or falling into despair. She especially loves Queen Celestia, and it is said that this love is tinged with a faint obsession. As the youngest, she uses polite language with all the other princesses and queens.