They cost £5.99 each so the boy wizard has helped the club make £60,000!
Before Harry Potter, the club only sold about 100 of the winter warmers a month.
Now they're selling so fast, the Bradford FC shop can barely keep up with the demand.
'Thanks Harry Potter!'
"They're selling tremendously," said a Bradford City spokesman. "Everybody wants them. It happened when the first film came out, and now with the second one too. When I first saw the film I thought: 'Oh my God! They're wearing our scarves.