Based on his doctors' advice, the Rock and Roll Hall of Famer has canceled the third leg of his 50th Anniversary tour, scheduled to arrive in Australia and New Zealand this March.
While the disease makes it difficult for Diamond to travel and perform, he'll still be able to write, record and get involved with new projects.
In a statement on his website, Diamond, 76, says, "It is with great reluctance and disappointment that I announce my retirement from concert touring. I have been so honored to bring my shows to the public for the past 50 years."
He continued: "My sincerest apologies to everyone who purchased tickets and were planning to come to the upcoming shows."
Diamond, who had hits like "Love on the Rocks" and "Sweet Caroline" over a career that has spanned five decades, said he planned to remain busy.
"I plan to remain active in writing, recording and other projects for a long time to come," he said. "My thanks goes out to my loyal and devoted audiences around the world. You will always have my appreciation for your support and encouragement.
"This ride has been ‘so good, so good, so good’ thanks to you,” he said.
Diamond will turn 77 on Wednesday. On Sunday, he'll be honored with the Lifetime Achievement Award at the 60th Annual Grammy ceremony.
Fans who purchased tickets for the tour via credit card or debit card will automatically receive full refunds. Fans who bought tickets with cash will be contacted to arrange their refund.