Rooney said she has spent five months attempting to work out who was leaking information about her and her family based on information she had posted on her personal social media page.
After months of detective work, Rooney claimed she has finally worked out it was "I'm A Celebrity ... Get Me Out Of Here!" star Vardy, the wife of Leicester City striker Jamie Vardy.
Rooney wrote on Twitter: "For a few years now someone who I trusted to follow me on my personal Instagram account has been consistently informing The Sun newspaper of my private posts and stories.
"There has been so much information given to them about me,my friends and my family - all without my permission or knowledge.
"After a long time of trying to figure out who it could be,for various reasons, I had a suspicion."
Coleen, who is married to former England captain Wayne Rooney, said she has spent five months attempting to work out who was leaking information about her.
Rooney, 33, said she "came up with an idea" to try to prove her theory that it was Vardy, and that she blocked everyone apart from her from seeing her Instagram stories.
She added: "Over the past five months I have posted a series of false stories to see if they made their way into the Sun newspaper.
"And, you know what, they did! The story about gender selection in Mexico, the story about returning to TV, and then the latest story about the basement flooding in my new house.
"It's been tough keeping it to myself and not making any comment at all, especially when the stories have been leaked; however, I had to. Now I know for certain which account/individual it's come from.
"I have saved and screen-shotted all the original stories which clearly show just one person has viewed them.
"It's ... Rebekah Vardy's account."
Rebekah Vardy has responded to the claims in her own Twitter account, saying she was "disgusted" she was having to deny the claims wile heavily pregnant.
"I like you a lot Coleen and I'm so upset you have chosen to do this," she said.
In the mist of the twitter feud Netflix have tweeted: "We're going to have to make a documentary about this, aren't we"