"Sales fell in 13 of 21 industries, representing approximately 45 percent of the manufacturing sector," the agency said.
The largest decline was in the aerospace manufacturing sector, where sales fell 33.7 percent to $898 million for the month.
Petroleum and coal product sales were down 4.9 percent to $7.1 billion while fabricated metal product producers had a 4.4 percent decline in sales to $2.9 billion.
On the plus side, motor vehicle assembly sales increased 9 percent to $4.5 billion.
"This was the 9th increase in 10 months for the industry," StatsCan said. "Sales were at their highest level since November 2007."