Heather (34), from Maghaberry, is a trainee at Stepping Stones NI, an organisation that provides training towards employment for people with learning disabilities.
She is also a trainee wedding stationery crafter in Pink Elephant Cards, a social enterprise of the charity, where she creates beautiful hand-crafted wedding stationery for brides and grooms across Ireland.
After hearing about Heather's wish to meet Jamie, the charity made it their mission to find the actor.
Chief officer Paula Jennings said: "I always knew Heather was a massive fan of Jamie.
"Last week, when I popped into Pink Elephant Cards and got chatting to Heather, she told me of her dream to meet Jamie Dornan.
"So I said then we would make it happen, not knowing how!
"It wasn't until later that I heard Jamie was filming in Belfast, and then I knew we had to make Heather's dream come true."
The actor - famous for playing billionaire playboy Christian Grey in Fifty Shades of Grey and serial killer Paul Spector in The Fall - said he was delighted to meet one of his biggest fans.
"It was a real pleasure to invite Heather down to the set of The Fall. She is a fantastic girl and it was wonderful to meet her," he said.
Heather was understandably over the moon with the surprise.
"I have been a fan of Jamie for a long time, but I never imagined my dream to meet him would actually come true," she said. "It was amazing to meet him and I am grateful to everyone who made it happen."
Heather presented Jamie with a gift of a picture frame made by trainees at Stepping Stones NI for his new baby, which is due to arrive in the next few weeks.
She also gave him a thank you card she had made at Pink Elephant Cards.
Stepping Stones NI is an award-winning charity that is based in Lisburn. It operates six social enterprises which serve as a training facility for adults with a learning disability or difficulty.