Dortmund lost the lead to a 1-2 defeat against Bologna in the Champions League, and thus noted their fourth consecutive defeat.
Now coach Nuri Sahin is being sacked.
"This decision hurts me personally, but it was unavoidable after the match in Bologna," says sports manager Lars Ricken to the club's website.
Sahin:
"Unfortunately, we have not been able to live up to Dortmund's ambitions this season. I wish this special club all the best."
Dortmund, which also only has one win in the last nine matches and is in 13th place in the Bundesliga, will next face Werder Bremen at home on Saturday,
It is unclear who will lead the team then.
