Analysts said that while export and import rates were still robust year-on-year, the latest data indicated a downward trend.
Imports rose 11 per cent to $146.9 billion, down from the previous month's 17.2 per cent.
Similarly, imports rose 11.0 percent in July from a year ago, much slower the expected growth of 18.0 percent.
The pace of growth of China's exports and imports weakened in July in a discouraging sign for the world's second-largest economy and global demand.
This could be explained in part by the negative effects of prices due to cooling producer price inflation, Capital Economics analyst Julian Evans-Pritchard says.
Reserves rose $24 billion in July to $3.081 trillion, compared with an increase of $3.2 billion in June.
The International Monetary Fund expects this year's economic growth to slip to 6.6 per cent from last year's 6.7 per cent and to below 6.2 per cent in 2018.
China has been trying to curb capital flight and risky bank lending, putting restrictions on property purchases as the country's mounting debt fuels fears of a looming financial crisis that could have global repercussions.
The trade surplus totaled $46.74 billion in July versus the expected surplus of $45.0 billion. Imports increased 14.7% to leave a trade surplus of 321.2 billion yuan (US$47.9 billion).
The Chinese trade surplus with the 28-nation European Union, the country's biggest trading partner, rose 3.4 per cent to $12.2 billion.