September's trade surplus was smaller than August's $17.8 billion and less than half of the $31.5 billion recorded in July. The annual pace of exports to the troubled European Union more than halved from August.
Exports rose 17.1 percent last month from a year ago, slowing from a 24.5 percent gain in August, and imports rose 20.9 percent, compared with August's 30.2 percent increase.
Still, the value of China's imports and exports are near record highs.
Compared to August, annual growth in China's electronics exports slowed by a third to around 13 percent, while that for high-tech shipments more than halved to 6.3 percent.
Annual growth in China's commodity imports also slowed. Crude oil shipments fell 12 percent from a year-earlier record level after holding steady in August.
For iron ore imports, annual growth more than halved to 15 percent compared to August, although the volume of shipments was at an eight-month high.
China's overall balance of trade with the United States, however, remained unchanged in September from August; in both months China recorded a $20.0 billion surplus.
China's trade surplus with the European Union was $12.9 billion in September, down from $14.8 billion in August.