The present invention relates to a canister for a gas mask using active carbon fiber to chemically filter contaminated air. The canister for a gas mask according to the present invention includes: a body which forms an inlet port on one side and forms an outlet port on the other side; a cover which covers the inlet port of the body and has an air inlet hole; a particle filter for removing particles from inhaled air; and a gas filter which purifies toxic gas in the inhaled air. The gas filter comprises activated carbon fiber. A plurality of ACF filters with a predetermined thickness and an edge of a predetermined shape capable of being accommodated in the body are laminated on the edge of the activated carbon fiber.
