The median forecast for expansion in gross domestic product (GDP), based on a poll of 18 economists, represents an easing from the second quarter's 6.7 per cent.
It would be the slowest quarterly growth since the first three months of 2009, in the middle of the global financial crisis.
As the world's biggest trader in goods China is crucial to the global economy and its performance affects partners from Australia to Zambia.
The AFP poll forecast China will just meet the goal, with the median full-year prediction at 6.6 per cent.
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"Our expectation is that growth will continue to slow. The largest headwind on the horizon is the housing sector, which peaked in April 2016 and thus is now in the correction phase of its cycle," Brian Jackson of IHS told AFP.
Beijing is trying to execute a difficult structural transition away from dependence on low-end exports and heavy industry toward consumption and services, but entrenched interests have slowed progress.
"Economic growth in the third quarter was better than market expectations," Rong Jing, a Beijing-based analyst with BNP Paribas, told AFP, but pointed to possible risks arising from the real-estate boom.
"The property bubble risk will continue to balloon if the government does not take tightening measures, as it would cause a very negative impact on the economy and the financial system," she added.
"The biggest restraint this year that prevents monetary easing is the real estate market."
Recent indicators have painted a mixed picture of China's economic health.
An official measure of manufacturing activity maintained its strongest level in nearly two years in September while auto sales grew at their fastest rate in three years in the world's biggest car market.
Data Friday showed that the price of goods at the factory gate rose in China for the first time in more than four years in September, a positive sign for demand after years of dropping prices battered manufacturers and put a damper on growth.