Kori Martin's offending garment said "Losers fight pitbulls" on the front and had Vick's name crossed out, the Philadelphia Inquirer said Wednesday.
Martin, 32, Broomall, Del., told the newspaper that security at Lincoln Financial Field would not let her in until she turned the T-shirt inside out.
She called the move an impingement of her right to free speech.
Martin said the guards told her that the shirt was offensive to the Eagles players and was to be barred under team policy. An Eagles official told the newspaper Tuesday she knew of no such policy.