Johjima held talks with his former team, the Softbank Hawks of the Pacific League, but decided instead to join the Tigers, signing a four-year deal worth $21 million.
"Hanshin was the first team to set up talks with me," Johjima said. "I'll do everything I can do to help the team win."
He opted out of the final two seasons and $15.8 million of his contract with the Mariners last week, allowing him to finish his career in Japan.
The 33-year-old Johjima hit .268 in four seasons with Seattle, with 48 homers and 198 RBIs in 462 games. He holds the American League record for hits by a rookie catcher (147 in 2006). His 18 homers in his first season tied the Mariners' record for most by a catcher.
He slumped to .227 as part of Seattle's 101-loss collapse in 2008 and hit just .247 in 71 games this past season, losing playing time to injuries and the Mariners' preference for rookie catcher Rob Johnson.