German factory orders fell in August by their largest amount since the height of the global financial crisis in 2009, according to official figures.
The economy ministry figures show that contracts fell 5.7% month-on-month, pointing to further weakness in Europe's largest economy.
The biggest drop was for orders from outside the eurozone, which fell 9.9%.
Germany's economy had a strong start to the year, but shrank by 0.2% in the second quarter.
Economists have warned that the economy could contract again in the third quarter, coming at the time when the eurozone as a whole is weakening.
Tensions over Ukraine have cast a cloud over trading between Germany and Russia. But Carsten Brzeski, senior economist at ING, said: "It's not only a [Russian President Vladimir] Putin fear factor - Germany is also suffering from the weakness of its eurozone peers."
The economies of France and Italy continue to struggle.
The weak data comes after a survey last week showed Germany's manufacturing activity shrinking for the first time in 15 months in September, as new orders dried up.
Germany's economic woes will be of great concern to the eurozone, which is battling persistently low growth and low inflation.
The European Central Bank introduced new measures to stimulate the area's flagging economy.
As well as launching an asset purchase programme, through which it will buy debt products from banks, the ECB cut its benchmark interest rate to 0.05%.