Leyland, at a news conference Monday, said he told Tigers players he was resigning after Saturday's loss to the Boston Red Sox in the AL Championship Series. He had informed Detroit General Manager Dave Dombrowski in early September he didn't want to continue as manager.
"I have told most all of you, when it's time, it's time. And it's time," Leyland said. "It's time to step down from the managerial position of the Detroit Tigers."
Leyland will be offered another position in the Tigers' organization, he said.
"Jim's tenure will be looked back on as one of the great eras in Tigers history, an era that included two World Series appearances, four ALCS appearances in eight seasons, three division titles and two American League pennants," Dombrowski said.
"It has truly been an honor to work with one of the great managers in the history of the game."
Leyland, 68, posted a 700-593 record while leading Detroit and helped the Tigers win the AL Central Division title each of the last three seasons.
Detroit was eliminated from the playoffs by Boston Saturday, losing the best-of-seven AL Championship Series 4-2. Leyland did take the team to the World Series twice but lost in five games to the St. Louis Cardinals in 2006 and in four games to San Francisco last year.
Detroit was the fourth managerial stop for Leyland. He led the Pittsburgh Pirates from 1986-96, twice being voted the NL Manager of the Year. Pittsburgh went to the NL Championship Series three times -- 1990-92 -- under Leyland.
He took over the Florida Marlins for 1997-98, taking the Marlins to the World Series title in '97. But the team sold off much of its talent and lost 108 games in '98, leading Leyland to resign. He also managed the Colorado Rockies in 1999.
Leyland's overall managerial record is 1,769-1,728. The wins total is 16th most all-time. Only two managers -- Sparky Anderson (1,331) and Hughie Jennings (1,131) -- won more games as manager of the Tigers.