Rowand, who played for the Giants the past four seasons, previously played for Miami manager Ozzie Guillen with the Chicago White Sox.
In 2005, Rowand batted .271 with 13 homers and 69 RBIs on the White Sox's World Series title team. The 2010 Giants became Rowand's second championship club.
A career .273 hitter, Rowand appeared in 108 games with San Francisco last year, hitting .233 in 331 at-bats.
Rowand, who can play all three outfield positions, provides veteran depth. The Marlins are expected to start Emilio Bonifacio in center field, but Rowand is an option there, if necessary.
Rowand broke in with the White Sox in 2001, and in addition to the White Sox and Giants, he has also played for the Phillies.