"Bye bye my blue" is a single album by Baek Ye-rin, released on June 20, 2016. It was composed by Kroom, with lyrics written by Kroom and Baek Ye-rin, and music publishing by JYP Publishing and Copyright Control.

The song is a ballad that sorrowfully sings about love that is fading away. Baek Ye-rin's emotional vocals and Kroom's beautiful melody blend together to touch the hearts of listeners.

"Bye bye my blue" received much love upon its release, and ranked high on various music charts. Additionally, the song has established itself as one of Baek Ye-rin's signature songs, and has been covered by many singers.