The University of Sheffield's Foundry said the event, due to be held on Thursday, February 8, "will be postponed".
Mr Young announced said the 52-year-old former model died after a two-year battle with brain cancer on Twitter.
She died peacefully at her home surrounded by her family, including her four children.
A statement from the star's publicist added: "The singer Paul Young has announced that his wife, Stacey Young, sadly passed away today after a two-year fight with brain cancer.
"Stacey died peacefully at home surrounded by family, friends and her four children: Levi, Layla, Grady and Jude.
"The family respectfully ask for privacy at this time."
It added that Mr Young hoped to reschedule the tour and will announce new dates as soon as possible.
Mr Young met Stacey on the video shoot for his 1983 hit Come Back And Stay.
They married in 1987 and have three children together - daughters Levi and Layla, and son Grady.