The agency calls the seizure "significant" and says the drugs were found in a large duffle bag that arrived on a flight from Argentina.
The agency says the bag contained six bricks of a substance that field tested positive for suspected cocaine.
CBSA says Peel regional police are investigating.
Police haven't said if any arrests have been made.
The agency says it made 180 cocaine seizures in the Greater Toronto Area last year totalling more than 954 kilograms.