"Number One Girl" is a track by Rosé, the South Korean singer and member of BLACKPINK. The song was released as part of her solo debut project in 2021, along with her single album titled R. Rosé's debut marked a significant moment in her career, showcasing her distinctive voice and artistry in a solo context.

The song itself features a blend of soft rock and pop influences, with Rosé's emotive vocals taking center stage. The track was well-received for its intimate feel, showcasing her ability to convey deep emotion through music. While "Number One Girl" didn't receive as much commercial visibility as her other songs like "On The Ground," it was still a favorite among many fans due to its personal and vulnerable lyrics.