The utility model relates to the technical field of gas masks, in particular to a canister adapter for
oxygen supplementation and a
gas mask, and mainly solves the technical problem that an
oxygen supplementation mode of an existing
gas mask is poor in universality. The adapter comprises a
barrel-shaped body, the inner wall of the
barrel-shaped body is divided into an internal thread section and an unthreaded hole section in the axial direction, the
diameter of the internal thread section is larger than that of the unthreaded hole section so that a first annular step face can be formed at the joint of the internal thread section and the unthreaded hole section, and the outer wall of the
barrel-shaped body is divided into an unthreaded shaft section and an external thread section in the axial direction. The
diameter of the
optical axis section is larger than that of the external thread section so that a second annular step face can be formed at the joint of the
optical axis section and the external thread section, the external thread section corresponds to the unthreaded hole section, the
diameter of the internal thread section is equal to that of the external thread section, and the unthreaded hole section is provided with an oxygenating connector communicated with the outside. When in use, the adapter is connected between a canister and a
mask body, is connected with an
oxygen supplementation device through the
oxygen supplementation interface on the adapter, can be suitable for various gas masks, and is high in universality.