The People's Commission, which has the support of 70 unions and advocacy groups, mostly from Quebec, says CSIS agents have been using intimidation tactics to pit activists against one another.
CSIS did not immediately respond to a request for comment.
The umbrella group says that, while CSIS has long tried to infiltrate activist groups, it has become more aggressive lately, particularly against anti-capitalist, First Nations and pro-Palestinian groups.
As a result, the organizations are advising their members to avoid talking or speaking with CSIS agents.
"We will not put ourselves, our neighbours, our friends, our families here or overseas, our organizations and our work for justice at risk by speaking with or listening to CSIS agents," said Marie-Eve Lamy, an activist with the network.
Amy Darwish, an pro-Palestinian activist, said CSIS agents have been questioning Arabs about their political views and about each other. By doing so, she says, they have in the past "succeeded in sowing fear and silencing support for justice and freedom in the Middle East."
"There were a number of members who were visited, invariably by agents who arrived unannounced, often early in the morning," she says.
"I would say it certainly had a chilling effect on our organizing work."
New female immigrants are often vulnerable and CSIS tries to take advantage of them, and as a consequence, they are reluctant "to speak out for their rights generally," says Dolores Chew of the South Asian Women's Community Centre in Montreal.
While most of the organizations that have signed on to the campaign are from Quebec, the network is hoping the movement gains steam across the country.
Chew says the spy agency's practices grew worse in the leadup to the Vancouver Olympics and the G20 summit in Toronto in 2010, when undercover police officers were embedded in various activist and anarchist groups.
Founded in 1984, CSIS has grown considerably over the past decade as it shifted toward counter-terrorism intelligence following the attacks of Sept. 11, 2001.
The agency had 3,104 employees in 2009-2010, over 1,000 more than a decade earlier.