The Xtra Factor presenter is rumoured to be dating the One Direction member, who was recently spotted leaving her home after spending the night there.
Styles's mum Anne Cox is apparently concerned about the new relationship and wants to meet Flack to give her approval, according to The Mirror.
A source said: "Harry has asked Caroline to meet his family this Christmas. And, after some persuasion she has agreed.
"Like any mother, Anne is concerned over the age gap but, if Harry can get his mother to see that Caroline makes him happy, that's all he wants."
Earlier this week, Flack laughed off questions regarding her relationship with Styles, describing him as "really nice" and "a lot younger than me".
She has previously insisted that their relationship isn't disgusting, saying the 15-year age gap isn't hurting anyone.