Retail investors check share prices at a securities brokerage in Fuyang, East China's Anhui province.
China's stocks dropped over 3 percent on market opening Friday after China and the U.S. announced reciprocal taxes on imports.
The benchmark Shanghai Composite Index opened at 3,172.77 points, down 2.78 percent on Friday morning.
The Shenzhen Component Index went down 3.37 percent to open at 10,511.16 points.
The ChiNext Index, which tracks China's NASDAQ-style board of growth enterprises, lost 3.60 percent to open at 1,751.71 points.
US President Trump signed a memorandum Thursday authorizing punitive annual tariffs of up to billion on Chinese exports under a Section 301 case on Chinese intellectual property policies and practices.
Then on Friday morning, China's Ministry of Commerce announced it is considering a tariff increase on imports of some products from the United States to make up for losses caused by the US tariff on steel and aluminum imports from China.
Analysts noted that fears of a trade war between the largest two economies in the world caused turmoil in the global stock markets.
On Wall Street, the major indexes suffered their biggest one-day percentage drop in six weeks on Thursday. The Dow Jones Industrial Average fell 723.45 points, or 2.93 percent. The S&P 500 lost 68.23 points, or 2.52 percent, and the Nasdaq Composite dropped 178.61 points, or 2.43 percent.
Hong Kong stocks lost 1,140.82 points, or 3.67 percent, opening at 29,930.23 points Friday.