Singing star Guest, 57, died surrounded by partner Kellie Dickerson, two teenage children, and other family and friends at Melbourne's St Vincent's Hospital.
The English born entertainer rose to pop fame in New Zealand in the 1970s when he began performing on the television show Happen In.
He also performed for 10 years in Las Vegas before his stage musical career took him to Australia where he starred in Les Miserables and The Phantom of the Opera.
He was made an officer of the Order of the British Empire (OBE) for his services to the New Zealand entertainment industry in 1994.
[comment caption=Share your memories of Rob Guest]Guest had been starring in the musical Wicked in Melbourne at the time of his stroke and played his last performance on Sunday night. New Zealand publicist for Wicked Sandra Roberts said the cast of the show would be "devastated".
"He's been a mentor to most of the cast behind the scenes, almost like a fatherly figure."
Musician and talent scout Gray Bartlett, who has been in the entertainment industry for 50 years, said it was a sad loss of a man he had known since the 1970s.
"He always had a great smile, a great enthusiasm and a tremendous charm and charisma.
"I think the thing that was really key to him being successful -- and he was really successful and probably one of New Zealand's greatest ever theatrical performers -- was the fact that he had the two ingredients that make a great performer.
"That is the ability to convey his emotion on stage and to show his fantastic imagination for his work." Bartlett said it was like losing a family member.
"He was just a wonderful guy.
"He died way too early. I can only say it's just a huge tragedy." Veteran singer and dancer Tina Cross was with Guest a week and a half ago after seeing his performance in Wicked.
She said he was "fantastic" when she saw him and his death today came as a shock she could not comprehend.
Cross and Guest worked together a lot in the 70s and 80s, performing here and in the United States.
She said she could take comfort in that he lived while still doing the work he loved.
Tim Beveridge, who was Guest's Phantom understudy, said he was shocked by the news.
"Rob was a great guy. He was a great role model in that he always gave it 100 percent every night."
Beveridge said he was generous to him and looked out for him whenever he became stressed.
"He was a very generous guy with a great sense of humour."
Beveridge recalled one time while working on the Phantom, Guest had tricked him into believing the cast was going to be flown across Antarctica.
"He told me to keep it a secret, but by the time I'd finished with it everyone in the cast heard about and it turned out it was false.
"He thought that was brilliant, but when he told me I was mortified."
Beveridge described him as a "great Kiwi bloke" who loved his fast cars.
Iconic pop singer Suzanne Lynch said Guest was at the top of his field when he died.
"It's a bit scary when it starts to hit the age group that we're all in."
She said he was a fabulous performer and singer.
"There's not a bad thing I can say. He was one of life's gentlemen."
Top New Zealand entertainer Ray Columbus said Guest would be sorely missed.
He said Guest was very devoted to his craft.
"He was a lovely guy, very professional, a fine singer and a great actor.
"It will be a great loss. you can't replace someone with his experience and his professionalism and his knowledge."
Broadcaster Paul Holmes, who presented the television biography show This is Your Life on Guest, said his death was "a terrible shock".
"His death makes me remember how much I liked him, and how I would have liked to have seen more of him," he said on NewstalkZB.
"He was a hugely talented man, he was a good bloke, he was a nice person, Rob Guest."
