BEIJING—China reported its largest-ever annual trade surplus with the U.S. last year while its overall imbalance with the world shrank, potentially strengthening the Trump administration’s case for tougher penalties and other trade actions against Beijing.

A global recovery led by the U.S. provided a shot in the arm for Chinese exporters last year, boosting China’s economy. Rising American demand, in particular, pushed up Chinese shipments, expanding China’s trade surplus in goods with the U.S. by 10% to $275.8 billion in...