Lee Minwoo was the 4th member to join the Korean boy band Shinhwa. During his years with Shinhwa, Minwoo developed his singing and dancing abilities. In 2003, he released his first solo album entitled Un-touch-able. It was during this time also that he chose a different solo stage name – choosing to be known as "M". Various songs which were proven to be extremely popular from M’s first album included Biya, Sweet Girl and Just One Night.

After hitting it big in 2003 from his first album, M decided to release a second. In September 2005, Lee Minwoo made public, IInd Winds, which has been a huge success with hit songs such as Last First Kiss, Bump and Girlfriend. These solo albums consisted of songs which he composed himself - a very great achievement for M as a soloist. July 2007 saw the release of a third jib called 'Explore'

And he just released his Fourth album, called 'MRizing' (Sept 2008).