"Whoever wants growth - and I trust this administration will be a growth-friendly one - must be in favor of open markets," Schaeuble told the Wall Street Journal in an interview.
"Protectionism can afford short-term advantages but is almost always damaging in the long term," he added.
The paper said Schaeuble was speaking before the publication of a Trump interview with German daily Bild, in which the president-elect threatened to impose a border tax of 35 percent on vehicles imported to the U.S. market.
Schaeuble also said countries must do more to counter attempts to influence politics via fake news, highlighting the high-profile case of a German-Russian girl who Russian media said was kidnapped and raped by migrants in Berlin, a claim later refuted by German authorities.
"Some people are being misled by fake news from Russian-language, state- financed and directed television," Schaeuble said. "One cannot describe this as anything but a propaganda war."
(Reporting by Paul Carrel and Victoria Bryan)
