She debuted in Super Mario Galaxy (2007), as a non-player character who resides in the Comet Observatory, the game's hub world.

It was written by Yoshiaki Koizumi late at night so that no one would find out about it, saying that "for a long time, it really felt like telling a story in a Mario game was something that wasn't allowed" in an interview.

[2] In another interview, Koizumi stated "I felt in this case that the Lumas and Rosalina really needed a story to explain what they were doing out there and to give the players a deeper understanding of their presence.

After this, Rosalina appears to Mario, explaining to him about the circle of life and the death and rebirth of stars; it is implicit in her explanation that the universe and all the Lumas are to be reborn.

As Rosalina starts to feel lonely, numerous other Lumas soon come to join her, and she learns that their purpose in life is to eventually transform into other things.

In Super Mario Galaxy 2, throughout the game, a shadowy form named the "Cosmic Spirit", strongly resembling Rosalina, appears to help in levels where the player has died multiple times.

"[8] In Super Mario Odyssey, she appears as an 8-bit sprite in the Dark and Darker Side of the Moon which can be hit by Cappy to collect ten coins.

[13] Joystiq commented on her appearance, saying that it was nice to see that another "Nintendo character join the obscenely large roster of folks showing their faces in the game.

Rosalina appears in Super Mario Maker as a Mystery Mushroom costume, which can be unlocked either through the 100-Mario challenge, or by scanning her amiibo figure.

[17] Douglas Wilson opined in GameSetWatch that Super Mario Galaxy's most surprising moment was Rosalina's storybook tale, stating that it "tackles the drama of human tragedy".

You’d think she’d have better things to do than whallop on Bowser Jr."[22] Gavin Jasper of Den of Geek ranked Rosalina as 33rd on his list of Super Smash Bros.

"[23] According to John Adams of his "Female Fighters: Perceptions of Femininity in the Super Smash Bros. Community" article from publisher Press Start, player response to Rosalina was positive about her gameplay and appearance.