"Although the trade data are often volatile, this latest decline (in import volumes)...is a sign that domestic demand may have weakened at the end of a year ago", Capital Economics Senior China Economist Julian Evans-Pritchard wrote in a note.
China's December imports missed market expectations, rising only 4.5 per cent year-on-year, while exports beat forecasts with 10.9 per cent growth, official data showed on Friday.
China's surplus with the United States is a hot-button issue with the Trump administration, which added new import tariffs to a number of Chinese goods past year.
"China's foreign trade continued to build on a solid foundation for steady growth, its potential being gradually unleashed", said customs spokesman Huang Songping.
General trade, which has a higher added-value than processing trade, increased both in volume and proportion in 2017, expanding to 15.7 trillion yuan and accounting for 56.4 percent of total foreign trade, up 1.3 percentage points from 2016.
"Import growth will slow too as China's economic expansion slows amid weaker investment in manufacturing and property".
Trump will have opportunities to impose tariffs on a range of Chinese goods. In the first half of 2017, Zhoushan Port handled 515 million tonnes cargoes, up 11.3 percent year-on-year, and 12.39 million TEU (twenty-foot equivalent unit) containers, up 14.6 percent year-on-year.
He estimated that imports declined by the biggest margin in nearly two years in volume terms in December as purchases of industrial commodities plummeted.
Compared to 2016, it said trade between the two nations fell by 10.5% a year ago. For comparison, the previous record was a surplus of $260.8 billion in 2015.
China's trade surplus with the European Union, its biggest trading partner, stood at US$14.6 billion last month.
Reuters reported last week that China will keep its target for economic growth at "around 6.5 percent" in 2018 -the same as in 2017.
In November, China stopped exporting oil products to North Korea, after the U.N. Security Council that month imposed new caps on trade with North Korea, including limiting oil product shipments.