Reus was expected to return after a long term lay-off with an adductor injury, but he has picked up a minor heel injury and will be out for the match against Dortmund's fierce rivals Bayern.
"[Marco Reus] has minor heel problems. In order to not risk anything given his very long absence, playing is not possible tomorrow," Dortmund said.
Meanwhile, Arjen Robben, Javi Martinez and Kingsley Coman are all out for Bayern, while Douglas Costa and Aruro Vidal are also doubtful.
"We had a lot of problems with the international matches," said Bayern boss Ancelotti. "Other teams have problems with their international players as well.
"The schedule in the European competitions is too full. I am no sports administrator but there has to be a solution".