Robin Hood, also known as Tim Pollard, appropriately met Sally Chappell at a banquet at the city's former Sheriff's Lodge venue.
The couple now have a two-year-old daughter called Scarlett.
Instead of wedding presents they have asked for donations towards a relaxing space for Ms Chapell, who has incurable breast cancer.
Mr Pollard, 52, said: "I think one of the first times I met her, I threw axes at her as part of the show.
"I can't say that will work as dating advice for everyone, but it did for me."
Speaking about his fiancÃ©e's cancer diagnosis, he said: "We both had a bit of a weep and now we are just carrying on anyway.
"We were planning on getting married, so that's what we're doing."
Mr Pollard has been playing Nottingham's famous outlaw for more than two decades.
He was in need of a Maid Marian so he asked Ms Chappell, who was also into re-enactments.
"It's the best chat-up line in the world really - 'Will you be my Maid Marian?'," said Mr Pollard.
"Except it wasn't a chat-up line. We worked together as Robin and Maid Marian for years just as friends and neither of us thought about going out with each other.
"And then five years ago, we just kind of went 'You know this pretending to be in love thing that we're doing? I quite like you' and we got together."
Ms Chappell, 39, is also a lecturer and researcher in human molecular genetics at the University of Nottingham.
"You can't pull the wool over her eyes about the seriousness of her condition because of her work but she has just been amazing with it," said Mr Pollard.
Ms Chappell said: "We've been a couple for several years now and even have a beautiful two-and-a-half-year-old baby daughter, Scarlett, so maybe it's time for me to make an honest man of Robin."
The couple are getting married later this month in Buxton, Derbyshire.
Guests will include the Pied Piper of Hamelin, from Germany.
Even Robin Hood's arch enemy, the Sheriff of Nottingham, has wished the couple well on their big day.
Jackie Morris, who holds the ceremonial role of the Sheriff, said: "I'm delighted the legendary love story of Robin Hood and Maid Marian, better known locally as Tim and Sally, is going to be celebrated on their wedding day.
"Tim dubbed me the 'nice' Sheriff, but even so I will leave him in peace on his wedding day. I'm sure family, friends, their daughter Scarlett and the Merry Men will help them celebrate in style.
"Myself and the whole of Nottingham will be celebrating with them in spirit and we wish them all the best for a happy wedding day."
Nottingham's official Robin Hood is to marry Maid Marian after they fell in love while playing the famous couple.