The world's second-largest economy expanded by 6.8 per cent in the April-June period, compared with a year ago, according to the median forecast of 12 analysts polled by AFP.
"Overall, the economy continued to show steady progress in the first half.but global instability and uncertainties are still relatively large, and the domestic long-term buildup of structural imbalances remains", said the statistics bureau in a statement.
The International Monetary Fund has forecast China's full-year growth for 2017 to hold steady at last year's level of 6.7% due to strong government spending.
The main Asian stock indexes fell on the data, before recovering to close the day at new highs.
Likewise, retail sales growth accelerated to 11% in June from 10.7% in May, while growth was expected to ease to 10.6%.
The GDP deflator, a gauge of economy-wide inflation, came in at 4.5 percentage points - the difference between the nominal and real growth rate of output.
The Communist Party has placed top priority on securing social and economic stability ahead of the congress, which is likely to consolidate President Xi Jinping's status as the most powerful Chinese leader in many years.
Craig James, chief economist at Commonwealth Securities in Sydney believes though that measures to be taken by the central bank will not be so severe.
The PBOC shifted to a modest tightening bias at the start of this year, guiding market interest rates higher during the first quarter, including immediately after the U.S. Federal Reserve raised rates in March.
The average rural residents' per capita disposable income reached 6,562 yuan in the first half, up 7.4 percent after deducting price factors, while that of urban residents increased 6.5 percent to 18,322 yuan. The trade surplus widened from $US40.8 billion in May to $US42.8 billion in June.
Meanwhile, data on Monday, which showed China's steel output hit a record in June, comes amid an investigation by the Trump administration into China's exports of steel and other metals.