Orders to German factories fell unexpectedly by 2.1% in October compared with the previous month.
Analysts had expected a recent upward trend in orders to continue.
The German Economy Ministry said "the pace of recovery seen in recent months weakened, but the trend in new orders is, however, still up".
Germany is Europe's biggest economy and the world's biggest exporter. It exited recession earlier this year.
The BBC reports falling orders from overseas were the main factor behind the overall drop.
Foreign orders fell by 3.5%, while domestic orders declined by 0.5%.
Orders in September were revised up to show a 1.3% rise.
