It is buying €3bn (£2.3bn) of euro-denominated bonds and $2bn of dollar-denominated ones.
Rumours on Wednesday that it was about to buy the debt sent Deutsche Bank's shares soaring.
The confirmation on Friday gave the shares a bit of a boost, although they had already been up by about 10% earlier in the day.
Deutsche Bank said that it had the resources to make the purchases without changing its funding plans.
"The bank's strong liquidity position allows it to repurchase these securities without any corresponding change to its 2016 funding plan," it said.
The buyback has been taken as a signal of the bank's robustness.
On Friday, German Finance Minister Wolfgang Schaeuble brushed aside concerns about the bank, whose shares fell to a 30-year low earlier in the week, saying Germany's largest lender was "strong".
"Deutsche Bank has enough capital," Mr Schaeuble said.
The shares fell 13% on Monday and Tuesday, despite assurances from the bank that its balance sheet was "rock solid".
Deutsche Bank has announced that it is to buy back more than $5bn (£3.5bn) of its own debt.