These new firings, which could widen to more than 500, according to Bloomberg's sources, comes after bonus payments that Chief Executive Officer John Cryan said were on the "generous" side, helped push the business in the red.
Cryan is trying to motivate and retain top investment banking staff, while keeping a lid on costs following three straight years of losses.
But with revenue at a seven-year low, even a relatively small increase in compensation can cause losses at the securities unit.
Chief Financial Officer James von Moltke has urged a return to more disciplined cost management after the lender scrapped a target for this year.
And these "generous" bonuses follow a 27% collapse in trading revenues and the disastrous debacle surrounding China's HNA liquidating its holdings of the giant German bank.