The Toronto club announced Thursday in Minneapolis, where the Jays have a series with the Minnesota Twins, that Guerrero was signed to a minor-league contract.
The Jays haven't said exactly how they plan to use Guerrero once he is called up.
"He has power off the bench ... which is something we are lacking," Toronto slugger Jose Bautista told the Toronto Star. "I think he's a great addition to this or any other team in the league. I'm surprised it took as long as it did for someone to sign him."
Guerrero had a one-year contract with Baltimore last season and then became a free agent. He hit .290 with 13 home runs and 63 RBI in 145 games with the Orioles.
The outfielder-designated hitter has a .318 batting average with 449 homers and 1,496 RBI in 16 seasons in the major leagues, mostly with Montreal and the Los Angeles Angels. He also played for Texas.
Guerrero won the American League Most Valuable Player award with the Angels in 2004.
He is to report to the Blue Jays' extended spring training in Dunedin, Fla.