The country's exports fell 0.3 percent in September from a year earlier, ending two consecutive months of rises, according to the General Administration of Customs.
Imports rose 7.6 percent last month from a year ago to 950 billion yuan ($154.3 billion), accelerating from September's 7.4-percent rise, the figures showed.
This left the country with a trade surplus of 192.38 billion yuan in October, down 3.3 percent year-on- year.
In the first 10 months of 2013, exports and imports gained 7.6 percent from a year earlier, with the trade surplus growing 12 percent year-on-year to 1.25 trillion yuan.
Trade with the European Union, the nation's largest trade partner, climbed 0.5 percent year-on-year during the January-October period, compared with a 0.8-percent decrease registered in the first nine months of 2013.
Trade with the United States, China's second-largest trade partner, rose 6.9 percent in the first 10 months, while that with Association of Southeast Asian Nations members increased 10.9 percent.
Trade with Japan, however, declined 7 percent, according to the figures.
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