Financial terms were not announced, but local media reported the deal worth $50 million.
"We are thrilled to add a premier hitter like Victor Martinez," Detroit general manager David Dombrowski said in a statement on the club's website (www.detroit.tigers.mlb.com).
"Our top off-season priority was to add a proven bat in the middle of our lineup and Victor is an established .300 hitter and run producer at the major league level."
Martinez, 31, hit .302 with the Boston Red Sox last season and has a career batting average of .300 during his nine seasons in the Major Leagues.
"We expect Victor to be in our lineup on a daily basis, serving primarily as our club's designated hitter and catching two to three times a week," Dombrowski said.
"He also has the ability to fill in at first base and his versatility allows us to keep a premier bat in our lineup every day," Dombrowski said of the four-time American League All-Star.
(Reporting by Gene Cherry in Salvo North Carolina, Editing by Tom Pilcher)