Jaesig Lee was born in Jinju (South Korea). He began his vocal studies in 1997 under Sungil Ha at the Jinju Mechanical Technology High School. From 2000–2005 he continued his education at the Korean National University of the Arts in Seoul (class of Gwangsun Song). In 2003 he took classes from Stoyan Popov in Sofia. He has performed the role of Alfred (Die Fledermaus) at the Seoul Arts Center and appeared in a gala concert at the Burgas Opera House (Bulgaria), a concert at the Musical Olympus festival at the Mariinsky Theatre, a Maria Callas memorial concert in Athe ns, the Maria Callas Grand Prix International Competition prize-winners’ concert and The Six Rising Stars gala concert at Carnegie Hall in New York in addition to numerous concerts in Korea. In January 2011 he performed at the gala presentation of the Musical Olympus festival at the Esplanade Concert Hall in Singapore.
In 2008 Jaesig Lee took part in three singing competitions in South Korea at which he won the Grand Prix and 1st and 2nd prizes. His next successes came with the Grand Prix at the Maria Callas Grand Prix International Competition in Athe ns (2009) and 2nd prize at the Marseille International Opera Competition (2009). In the summer of 2010 Jaesig Lee won 1st prize at the Wilhelm Stenhammar International Singing Competition in Sweden and in December 2010 he won the 1st prize at the Giovanni Batista Viotti International Competition in Parma.