The 30-year-old featured at two Winter Olympics - in Turin and Vancouver in 2006 and 2010 respectively - and ended his 11-year career ranked 12th in the world in the super-combined.
"Although I can't say I stood on the top step of a World Cup podium, a childhood dream of mine, I can say I gave it my all," Semple said.
"I have represented Canada in two Olympics, three world championships and finished among the top 15 in the world. I am truly privileged to have accomplished these great feats which very few have had the honour."
Semple admitted his fitness was a factor in his decision to call time on his career.
"In order to achieve my goals, I needed to feel both mentally and physically consistent, which is something I struggled with throughout the last couple of seasons," he said.
Fellow Canadian Erik Guay paid tribute to his team-mate.
"He is a heck of a person and friend," Guay said. "I'm sure he's going to have no problem translating his work ethic as an athlete into the next phase of his life."