"One Fine Day" is a song by South Korean musician Jung Yong-hwa of CNBLUE. It was released on January 20, 2015, as the lead single from his debut solo album of the same name. A breakup ballad, the song's narrator describes the relationship with a former girlfriend and recollects his memories of the time they spent together.

One Fine Day is the debut solo studio album by South Korean musician Jung Yong-hwa of CNBLUE. It was released on January 20, 2015, by FNC Entertainment and distributed by CJ E&M. As CNBLUE's promotions for their mini-album Can't Stop (2014) came to a close, the label announced plans for Jung to release a solo album within the year. Since the album's inception, he sought to distance himself from the band's sound and include various musical styles on the record. Ultimately, he conceived a collaborative album with an array of musicians.