Deutsche Post bought DHL in 2002
Deutsche Post is to cut 9,500 jobs at DHL Express in the US and scale down the operations of the US business.
Deutsche Post also said it would scrap DHL Express's US domestic-only air and ground operations to focus entirely on its international business.
The cuts come on top of the 5,400 jobs that have already been shed at the unit since the start of the year.
Deutsche Post, Europe's biggest mail carrier, bought DHL in 2002. DHL's main US competitors are UPS and FedEx.
The cutbacks at DHL Express will cost about 3bn euros ($3.9bn, Ł2.4bn), but Deutsche Post said it should cut operating costs at the US business from $5.4bn to less than $1bn.
Currently there are some 18,000 workers in the express unit.
Deutsche Post said the US remained a key market.
"The international express offering in the US will be maintained on today's levels and the region will remain an integral part of DHL's global Express network," the company said.
The company reported a jump in its third-quarter net profit, which more than doubled to 805m euros compared with the same period a year ago.
But Deutsche Post said the restructuring would lead to a net loss of 1.2bn euros in 2008 and 700m euros in 2009.
Investors appeared to welcome the cost-cutting move as Deutsche Post shares ended Monday trading up 6.9%.