The Canadian Food Inspection Agency says the retail giant is not reliably following food safety controls on a consistent basis.
The agency says Costco is in violation of federal fish inspection regulations and the suspension on imports went into effect on Feb. 26.
It says there is no product recall associated with the licence suspension.
Costco Canada officials were not immediately available for comment.
The company's website indicates it operates 89 warehouse store locations across Canada.
"The CFIA has determined that adequate controls for food safety are not being reliably implemented by the company on a consistent basis, which is in violation of the Fish Inspection Regulations," the agency says on its website.
The CFIA says Costco can't import fish products into Canada until is takes corrective action and the agency is satisfied that the chain can effectively manage food safety risks.
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