The Canadian stocks went down on Thursday with the S&P/TSX Composite Index closing down 118.07 points, or 0.98 percent, at 11911.89.
The S&P/TSX Venture Composite Index closed down 10.14 points, or 0.66 percent, at 1,532.63.
The Chinese economy has been a main support for the world economy. China's exports were 17.1 percent higher in Sept. than the same period a year earlier, much slower than the 24.5-percent year-over-year gain in August. Commodity futures declined under the influence of the news.
The index measuring the diversified metals and mining sector on the Toronto Stock Exchange (TSX) dropped 2.37 percent as copper futures lost ground. Lunding Mining Corp. reduced 2.99 percent. First Quantum Minerals Ltd. dropped 4.24 percent.
Gold stocks were also big losers as gold futures declined. The index measuring the materials sector on the TSX decreased 1.28 percent. Barrick Gold Corp., the world's largest bullion producer, shed 2.00 percent.
Financial stocks pressed the markets as well. The index measuring the financials sector on the TSX lost 1.41 percent. Royal Bank of Canada, the country's biggest lender, slipped 2.07 percent.
On Corporate news, Air Canada said that its flights are operating on schedule after the federal labor minister blocked a planned strike by flight attendants just hours before it was set to begin.
Magna International Inc. said that it was being investigated by the U.S. Justice Department on an antitrust matter in the auto tooling industry. The Canadian auto parts giant said that it was cooperating in the investigation, which centers on tooling contract bids by its Cosma International unit.
On the economic front, data released by Statistics Canada showed that Canada's trade deficit with the world widened from 539 million U.S. dollars in July to 622 million U.S. dollars in August, with both imports and exports growing.
On the currency front, the Canadian dollar weakened against its U.S. counterpart.
One U.S. dollar was buying 1.0205 Canadian dollars at 5 p.m. local time (22:00 GMT) on Thursday, compared with one U.S. dollar purchasing 1.0173 Canadian dollars on Wednesday.