Norman, 55, said he surprised mother-of-two Kutner with a six-carat diamond ring, a moment he described to Australia's New Idea magazine as "perfect".
"One minute we were having a day-to-day conversation and the next moment, all of a sudden, everything changed -- our lives changed," Norman said, in a preview of the magazine interview published by AAP.
Kutner said Norman, 14 years her senior, was the "big love of my life."
"I am definitely the luckiest woman on this earth. I am so blessed to have such an amazing man to share my life with," she said.
Norman split from tennis player Chris Evert, his second wife, at the end of 2009. His first marriage, to flight attendant Laura Andrassy, ended in 2007 after 25 years.
Nicknamed the "Great White Shark" Norman was formerly ranked number one in the world and won the British Open in 1986 and 1993.
