LaMar, who spent 10 years with the Rays, most recently served as the assistant general manager for player development and scouting with the Phillies. LaMar was with the Nationals in 2007, and he worked with Pittsburgh, Cincinnati and Atlanta before his tenure with Tampa Bay.
Andrew Tinnish, Toronto's director of amateur scouting, issued a statement about the hiring.
"With over 25 years of experience we welcome Chuck's insight and expertise," said Tinnish as part of a press release. "I look forward to the contributions he will make to our scouting team as we continue to prepare for the 2012 First-Year Player Draft."
LaMar became the first general manager of the Rays when he was hired in July 1995. He experienced mixed results in free agency and trades but excelled through the First-Year Player Draft and has received some of the credit for the club's recent success.
The 55-year-old LaMar drafted the likes of outfielders Josh Hamilton, Carl Crawford, B.J. Upton and Rocco Baldelli. LaMar also selected pitchers such as James Shields, Andy Sonnanstine and Jeff Niemann.
LaMar became available after he resigned from his post in Philadelphia in September. The move came as a surprise at the time and was described as a "disappointment" by Phillies general manager Ruben Amaro Jr. LaMar had been in charge of overseeing the Phillies' Minor League system.
The move is the second piece of good news to hit the Blue Jays' front office this week. It was announced on Tuesday that assistant general manager Tony LaCava had turned down a job offer with the Orioles to remain in Toronto.
The Blue Jays also announced on Friday that they have promoted area scout Rob St. Julien to regional crosschecker and that West Coast video coordinator Brian Johnson has been elevated to area scout.
Gregor Chisholm is a reporter for MLB.com. Read his blog, North of the Border, and follow him on Twitter @gregorMLB. Spencer Fordin is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.