According to the Financial Times, the Bundesbank has launched a probe against Germany's biggest lender concerning the accusations dating back to 2011.
The newspaper alleged that three former Deutsche Bank employees told US regulators, the SEC, that the bank had used improper accounting to misrepresent as much as $12 billion (€9.3 billion) in losses on credit derivatives during the financial crisis between 2007 and 2009.
Deutsche Bank – which liked to present itself as one of the few German banks to weather the crisis – hid the losses so as to avoid a government bailout, said the FT.
The Bundesbank said it always examines allegations of wrongdoing by Germany's banks, but could not provide information about individual investigations.
"We cannot provide any information about supervisory measures concerning individual banks," a spokeswoman said.
"But in principle it is true to say that the central bank looks into whether any accusations are valid," she said.
Deutsche Bank has always denied the allegations, issuing a statement on Thursday dismissing the report as "wholly unfounded".
It said the allegations were "more than two and a half years old" and had been widely reported in June 2011.
"The investigation also revealed that the allegations stem from people without responsibility for, or personal knowledge of, key facts and information," it added.
Deutsche Bank has said it had properly valued and accounted for its trading on the credit derivatives in question and the positions had since been unwound in an orderly fashion.
Deutsche Bank booked a net loss of €3.9 billion in 2008, but ran up a profit of nearly €5.0 billion in 2009.