China's economy grew 6.7 percent in the second quarter from a year earlier.
Exports have been a drag on the economy for some time as shipments have declined on weak external demand.
Shocks from Brexit could also hurt one of China's biggest export markets.
Some analysts argue that Beijing has been too cautious in lowering rates and freeing up cash in the banking system, keeping real interest rates too high given low returns on investment.
After a year of heady gains, Chinese markets have been buffeted by increasing signs that economic growth is faltering.
The Shanghai Composite Index eased 0.2 percent in subdued trading on Wednesday morning.
More than 1,500 shares listed in Shanghai and Shenzhen dived by the daily limit.
It has been a difficult year for the world's second-largest economy.
A series of modest support measures from the government over the year helped stave off worries of a more dramatic slowdown
China has relaxed its one-child policy and further freed up markets in order to put the world's second-largest economy on a more stable footing.