Statistics Canada says manufacturing sales fell 0.4 per cent to $58.6 billion in August, due to a drop in motor vehicle sales.
Economists had expected a drop of 0.6 per cent, according to Thomson Reuters Eikon.
Sales were down in seven of 21 industries tracked, representing 50.9 per cent of the Canadian manufacturing sector.
The motor vehicle industry saw sales fall 8.3 per cent to $4.9 billion in August, due to shutdowns in some assembly plants in August.
Excluding the auto sector, overall manufacturing sales were up 0.4 per cent in August.
The overall volume of sales in the manufacturing sector were down 0.3 per cent in August.