Suzy's track for the 'While You Were Sleeping' OST has been released!

SEE ALSO: Suzy stars as 'First Love' in Epitone Project's MV

Suzy is the voice behind "I Love You Boy", the theme song for the character she plays in the SBS drama. The track reveals Hongjoo's (Suzy) growing feelings for Jaechan (Lee Jong Suk), and viewers will hear it in the second half of the series.

This isn't the first time Suzy has participated in the OST for a drama she's starring in as she previously sang theme songs for 'Dream High' and 'Big'. Check out the song above!