Financial details were not disclosed by the English Premier League (EPL) clubside, but British media reported the transfer fee was 23 million euros (20.73 million pounds).
Torres scored six goals and had eight assists for Valencia in all competitions last season as they came ninth in the Spanish La Liga.
“I am so happy to be joining Manchester City. Every player wants to be involved in attacking teams and Manchester City are one of the most attacking in world football,” Torres told the club website.
“Pep (Guardiola) encourages a really open, aggressive style, which I love, and he is a manager with a proven track record of improving players. To have him overseeing my development is a dream.”
Torres joins Manchester City as a replacement for Germany winger Leroy Sane who moved to Bundesliga champions Bayern Munich last month for 45 million euros plus add-ons.
“He’s young and still developing, but his technical qualities are exactly what we are looking for in a winger,” Manchester City’s director of football Txiki Begiristain said of Torres.
“He’s quick, direct, can create space with one movement and is capable of producing match-winning moments.”
This is noteworthy as Guardiola looks to close the gap on Premier League champions Liverpool next season.
Second-placed Manchester City finished 18 points adrift of the Anfield side but won the League Cup and are still in the UEFA Champions League.
They lead Real Madrid 2-1 ahead of their last 16 second leg home match on Friday.(Reuters/NAN)