Trade surplus versus the U.S. rose to a record $28.1 billion.
China's overseas shipments rose from a year earlier, narrowly missing estimates, the latest sign that Asian trade is holding up on robust external demand and a brighter global outlook.
As result, the trade surplus totaled USD28.47 billion in September versus the expected level of USD38.0 billion.
The surplus with the United States reached 28.1 billion in September, up from 24.9 billion in September of previous year. The surge in imports shows demand in China is strong.
It is good news for President Xi who is expected to secure a second five-year term as general secretary of the Communist Party during its twice-a-decade congress, which opens on Wednesday.
With China's support, the United Nations has agreed on two rounds of sanctions since the beginning of August including bans on North Korean exports of iron, coal, lead, seafood, textiles, and oil import restrictions.
Imports for the first three quarters were 3.44 million tonnes, down 9.4 percent on the same period past year, customs said.
"Nonetheless, today's figures suggest that not only has strong foreign demand continued to prop up manufacturing activity in China but domestic demand remains resilient, too", Evans-Pritchard said. The surplus grew to $28.08 billion from $26.23 billion in August.
It was a better performance than August, when exports rose 5.5 per cent and imports were up 13.3 per cent.
That could aggravate President Donald Trump's frequent complaints that the trade balance between the two nations hurts the USA economy.
Nevertheless, fishermen and seafood traders said smuggled seafood was still moving across the border. China's exports to North Korea dropped a more modest 6.7 per cent in September, Huang Songping, spokesman for the customs department, told a news conference. US officials have resumed criticizing Chinese policy after President Donald Trump said in April he would temporarily shelve disputes while Washington and Beijing cooperated on North Korea.
China's economy has surprised analysts with its resilience so far in 2017, expanding by 6.9 percent in the first half, though most market watchers have stuck to predictions that it would lose some momentum in coming months.
That could see a further rise in borrowing costs for companies and consumers.