Customs data issued Friday showed exports rose 10.9 percent in December over a year earlier to $231.7 billion, down from the previous month's 12.3 percent growth.
Imports had been forecast to rise 13.0 per cent, softening from an 17.7 per cent gain seen in November, with the trade surplus tipped at US$37.0 billion last month from November's US$40.21 billion.
China's exports to North Korea also declined, down 23.4 percent from a year ago to $260 million in December, Huang Songping, customs spokesman said in a briefing in Beijing.
China may face a trade deficit within the next five to 10 years as the next phase of the economy's development will require the country to ramp up imports, according to one of China's top economists.
It will be hard to keep double-digit trade growth this year given the many global uncertainties and a high comparison base, Huang said.
Helping to explain the significant increase in the headline trade figure, export growth topped expectations while import growth decelerated sharply.More news: Trump comment on 'shithole countries' extremely offensive - Jessie Duarte
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"Import growth will slow too as China's economic expansion slows amid weaker investment in manufacturing and property".
Just how badly could Trump's threatened 45pc tariff hurt China? Iron ore imports for the year hit a record high of 1.075 billion tonnes.
Despite the strong year, moment is likely to wane, with surveys showing falling confidence and new orders in December. "A major uncertainty is potential China-US trade frictions".
However, Kujis of Oxford Economics believes import growth will only soften moderately this year, as the Chinese government has been careful not to let its tightening measures deal blows to the economy.
"However, later this year, we believe real effective exchange rate appreciation and an increase in USA protectionism could weigh on Chinese export growth, narrowing the trade surplus further".