Though most of her music is released in Japan, she does her work primarily from Gotland in Sweden, mainly doing promotional videos, photo shoots and recording there.
She originally debuted in 1999 under Universal Music Japan using her real name, Watanabe Mizuki, releasing two singles.
In 2003, she began working with the Swedish producer Tord Backstrom and debuted under Victor Entertainment with the pseudonym Miz in 2004.
In 2007, Watanabe returned to Universal Music Japan, changed her stage name to Mizrock, and released her first mini-album Good bye, yesterday and three singles.
Her biggest hits in Japan are "New Day" and "In The Sky", the theme song for the Square Enix role-playing video game Grandia III.
At this time there was held a talent competition, with advertising posters put up in over 20,000 beauty salons all over Japan.
Five months later, she released a second single called "Ambition"(PlayStation game Kouklo Theatro's theme song).
She was introduced to a producer named Tord Bäckström, who was looking for someone to perform a song written by a Swedish writer.
To promote her first Japanese album, Miz was invited to a Channel V-hosted concert in Taiwan along with other local and foreign artists, where she performed three songs, "New Day"", Waiting for" and "Say It's Forever".
In November, Miz released a separate, English language album in Sweden called Story Untold, but it failed to get into the top 60.
Two new singles were quickly released in the following months: a Japanese version of "Backseat Baby" from her Swedish album in late 2005 and a completely new song, "Bittersweet", in 2006.
Other websites such as ORICON and Tower Records confirmed this, listing a mini-album titled Good bye, yesterday to be released under the name "Mizrock".