HMCS Chicoutimi is deployed to the Asia-Pacific region until March, according to the navy.
The diesel electric sub, purchased from Great Britain in 1998, is part of an international operation called Poseidon Cutlass, a Royal Canadian Navy spokesman said in an email from Ottawa.
The sub left CFB Esquimalt last month and will engage with a variety of ships from other navies, the navy said.
The exact location and commitments of Chicoutimi were withheld.
Two Esquimalt-based warships, HMCS Ottawa and HMCS Winnipeg, returned from Poiseidon Cutlass in August after a five-month deployment.
The vessels visited 14 ports in 10 countries and worked with ships belonging to other Pacific countries, including the U.S., Australia, China, Chile, Japan, Korea, India, Indonesia, Korea, New Zealand, Sri Lanka, Singapore and Vietnam.