It is thought that Tito Vilanova will be looking to bring a new centre half to the Nou Camp this summer and Hummels has followed Paris Saint-Germain's Thiago Silva in making his interest public.
The 24-year-old came through the ranks at Bayern Munich, but only made one appearance before moving to Dortmund in 2009.
He told Sport Bild: "My father and I reject 99.9 per cent of all clubs around the world when they let their interest be known.
"But Barcelona is one of two or three clubs that would make me listen to them if they did make a move for me.
"I would have to look at it, but I am not saying that I want to go."
Barcelona reportedly favour a move for Hummels over Thiago Silva, while Lyon's Croatian star Dejan Lovren is also on the shortlist, according to El Mundo Deportivo.