The 61-year-old Connecticut native agreed to terms on a two-year contract with club options for 2014 and 2015. Financial terms were not disclosed.
"We are thrilled to welcome Bobby as the manager of the Red Sox, and I'm eager to begin working closely with him in our preparations for the 2012 season," said BoSox general manager Ben Cherington. "He is one of the brightest baseball minds I have encountered, with a wealth of experience in the game, an unmatched passion for winning and a proven track record of success in demanding environments. In Bobby, we have the right man to lead the Red Sox."
It will be Valentine's first MLB job since he was fired in 2002 after six-plus seasons managing the New York Mets. Valentine also managed the Texas Rangers for parts of eight seasons (1985-92) and owns a 1,117-1,072 regular season record in the majors.
He also proved to be a successful manager in Japan with the Chiba Lotte Marines of the Pacific League, winning a Japan Series title in 2005.
In addition, since being fired by the Mets, Valentine served a TV analyst and has held the position of director of public health and safety for the city of Stamford, Connecticut since January.