The flat showing was the first month without growth since the start of the year, the data agency said.
The mining, and oil and gas industry shrank by 1.5 per cent. Manufacturing expanded by one per cent and the public sector by 0.5 per cent.
Economists had been expecting slight growth of about 0.3 per cent, so the showing was a disappointment, especially after there were signs of the economy heating up earlier in the summer after a bitterly cold winter across Canada that put a chill on growth.
"North America’s autos rebound wasn’t enough to make up for weakness in the natural resources sector in July," Scotiabank said in a note to clients.
The monthly figure means Canada's economy is chugging along much more slowly than its southern neighbour, where business is booming.
The latest data out of the U.S. shows the American economy was expanding at a 4.6 per cent pace heading into the summer.
"The latest GDP data suggests that the economy had less underlying momentum at the start of this quarter than most had expected," David Madani of Capital Economics said of the Canadian numbers. "Accordingly, this reinforces our view that the Bank of Canada will be in no hurry to raise interest rates anytime soon."