"If all countries follow the example of the United States, this will undoubtedly result in a serious impact on the international trade order," foreign ministry spokeswoman Hua Chunying told a regular news briefing.
Hua repeated China's commerce ministry's position on steel and aluminium tariffs, saying the US has taken over 100 counter-measures against imports of the products amounting to "excessive protection for domestic products."
Trump announced the new tariffs as Liu He, a top advisor to President Xi Jinping, is visiting Washington on a mission to smooth out trade relations between the world's two largest economies.
"They candidly exchanged their views, building the necessary conditions for the next step in deepening cooperation," Hua said.