The former contestant on The X Factor broke down in tears when he heard that he had triumphed in the Channel 5 show.
US reality TV couple Speidi were the runners-up (counting as one housemate) while Neighbours star Ryan Maloney had earlier finished in third place.
Steps singer Claire Richards finished fourth and footballer Neil Ruddock fifth.
Rylan told presenter Brian Dowling: "Coming from you, this is a dream come true.
"For the past year, all people have been doing is picking up a phone for me, and I really appreciate it with all my heart."
And claimed he didn't understand how he had won, because he had been "hated... three months ago".
There was a touching moment when he spoke to his mother on the telephone and he asked her: "can you believe it?"
"I can believe it, 'cause you've been yourself," and replied, adding that she was "dead proud" of him.
Rylan also praised his new BFF Claire, saying: "She is everything I wanted her to be and more. I can't wait to meet her kids, meet Reece her husband... and I'll get to meet H from Steps as well.
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