During 2005-2010, Kim has had three solo songs from SS501 albums: "Hikari" from Kokoro,"Kokoro (First Press Limited Edition C)(Japan Version) info" YesAsia. Retrieved 2012-10-09. "Never Let You Go" from U R Man,"SS501 Special Mini Album - U R Man info" YesAsia. Retrieved 2012-10-09."Special Album (First Press Limited Edition)(Japan Version) info" YesAsia. Retrieved 2012-10-09. and "Wuss Up" from SS501 Solo Collection."SS501 - Collection info" YesAsia. Retrieved 2012-10-09. In 2009, he contributed a soundtrack from Bad Girl OST named "Lonely Girl" with Kim Hyung-jun."Bad Girl Diary OST info" YesAsia. Retrieved 2011-11-23.
