Statistics Canada released the trade data on Tuesday. Canada's trade deficit widened to C$2.53 billion in August from a deficit of C$0.82 billion in July. July's figure was revised up from a deficit of C$0.59 billion.
Analysts had expected a trade deficit of C$1.2 billion.
The increase in deficit was driven by a drop in exports. Exports slid 3.6% in August.
Exports of energy products dropped by 14.7% in August, exports of consumer goods dropped 8.0%, exports of motor vehicles and parts rose 3.1%, while exports of metal ores and non-metallic minerals were up 15.7%.
Imports climbed 0.2% in August.
Imports of aircraft and other transportation equipment and parts plunged by 14.4% in August, imports of metal and non-metallic mineral products climbed 6.0%, while imports of electronic and electrical equipment and parts declined 7.9%.