Fearing a recession due to drastic interest rate increases in the USA and the euro zone, further investors withdrew from the German stock market at the beginning of the week.
At the opening on Monday, the Dax fell by one percent to 12,839 points.
On Friday, US Federal Reserve Chairman Jerome Powell prepared the financial markets for a longer series of significant interest rate hikes.
Similar statements were made by leading members of the European Central Bank (ECB).
"The Fed sees its top priority as ensuring price stability and, in this context, bringing inflation back to its target of 2 percent," said Commerzbank analyst Thu Lan Nguyen.
"If in doubt, they would also accept a recession for this."
At the ECB, however, some investors doubted that the central bank would be able to sustain a tight interest rate hike.
After all, they have only hesitantly tightened monetary policy so far.
Bayer was one of the biggest losers in the Dax with a price drop of 2.9 percent after the pharmaceutical company published test results for its anticoagulant Asundexian.
The drug missed its primary target in terms of effectiveness, commented analyst Charlie Bentley of investment bank Jefferies.