Weekend reports suggested the odd couple was an item, with some gossips suggesting the Oscar winner might attend the Emmy Awards with the funnyman on Sunday night (23Sep12).
But Stonestreet, who recently revealed he had split from actress Katherine Tokarz at the beginning of 2012, has taken to Twitter.com to dismiss the latest romance rumours.
He jokes, "I wish people would stop spreading rumors that Charlize Theron and I are dating. Its starting to make Halle Berry jealous."
Meanwhile, the actor's representative tells People magazine, "There is nothing romantic going on between them. He has only met Charlize twice."