The 30-year-old from Pont-Rouge, Que., touched in a time of two minutes 7.61 seconds, ahead of silver medallist Aimee Willmott of England (2:08.07) and bronze medallist Maddie Groves of Australia (2:08.44).
It's the third swimming gold of the Games for Canada. Ryan Cochrane won the men's 1,500m freestyle, and Katerine Savard took the women's 100m butterfly.
Earlier Monday, Canada's Brittany MacLean captured a bronze medal in the women's 800 freestyle.
It was the second medal in Glasgow for the 20-year-old Toronto native, who helped Canada to silver in the 4x200-metre free relay on Saturday.
"I had so much fun getting the silver the other night with the relay team, but I really wanted to do one also individually," MacLean said.
She finished in eight minutes 20.91 seconds Monday, shattering the Canadian record she set at the national trials in the spring by four seconds.
Jazz Carlin of Wales won the gold in 8:18.11, a Commonwealth Games record. Lauren Boyle of New Zealand was second in 8:20.59.
MacLean, who finished fifth in Thursday's 200-metre freestyle, will race in the 400-metre freestyle on Tuesday.
Canada has also won three medals outside the pool so far on Day 5.
Sultana Frizell repeated as the gold medallist in the women's hammer throw, weightlifter Marie-JoséeArès-Pilon took bronze in the women's 69-kg division, and Tim Nedow captured bronze in the men's shot put.