Kim Sunggyu was born on April 28, 1989 in Jeonju, South Korea. He attended Jeonju National University High School and was in the school rock band called “Beat.”
When Sunggyu first told his parents about his dream to become a singer, they rejected it because they wanted him to have a normal life and told him they’d rather he leave the house instead. He continued to practice in secret and came to Seoul alone to pursue his dreams after graduating from high school.
In 2007, he auditioned for SM Entertainment but failed to make the cut, and auditioned once more in 2008 only to fail again.
Due to his admiration for rock band Nell, he initially auditioned at Woollim Entertainment under the recommendation of Nell’s manager whom he’d met coincidentally at the cafe he worked at part-time. With a hurting stomach, Sunggyu went to his auditions and lightly threatened them by saying, “If you don’t pick me, I’m going to bother you forever.” Afterwards he rushed to hospital immediately and got an appendectomy. On the day of his release, he received notification that he had passed his audition.
Originally intending to pursue rock music like was his dream, Sunggyu instead became a trainee for dance group Infinite of which he would later assume the positions of Leader and Main Vocalist, only to be criticized by his school friends who questioned whether someone like him should be debuting as an idol when his passion clearly lied in rock music.
In 2010, Sunggyu finally made his debut with Infinite on June 9.