The forecast was carried by the official Xinhua news agency ahead of Friday's official announcement of the key quarterly economic numbers, including the gross domestic product.
Lu Zhengwei, chief economist with the Industrial Bank, said the year-on-year GDP growth will ease to 7.8 percent in the second quarter, while industrial output will grow around 9.8 percent, Xinhua reported.
Researcher Wang Tianlong at the China Center for International Economic Exchanges said the indicators are likely to fall further as suggested by the weakening purchase management index (PMI), which measures manufacturing activity. The PMI growth, announced this month, fell to a seven-month low of 50.2 percent in June, slightly higher than the crucial 50 percent level.
China's central bank, which has cut benchmark interest rates twice this month, also expects worse-than-expected data.
First-quarter GDP growth slowed to a near-three-year low of 8.1 percent in the world's second-largest economy because of measures to cool inflation as well as gloomy global markets.
China in the previous 10 years has averaged GDP growth rates of more than 10 percent.