A hollow fiber degassing module comprising: a hollow fiber membrane bundle including a plurality of hollow fiber membranes bundled into a cylindrical shape; a housing that houses the hollow fiber membrane bundle, includes a liquid supply port and a liquid discharge port that are formed in communication with spaces between the plurality of hollow fiber membranes, and further includes a suction port formed in communication with inner spaces of the plurality of hollow fiber membranes; a first sealing portion that fixes one membrane bundle end portion of the hollow fiber membrane bundle; and a second sealing portion that fixes the other membrane bundle end portion of the hollow fiber membrane bundle, wherein: in a cross section passing through the one membrane bundle end portion and orthogonal to an axial direction of the housing, the first sealing portion fills an entire region in the housing except for a hollow portion of the hollow fiber membrane bundle to form a communication port that serves as an opening of the hollow portion and allows communication between the hollow portion and the liquid supply port; and in a cross section passing through the other membrane bundle end portion and orthogonal to the axial direction of the housing, the second sealing portion fills an entire region in the housing except for the inner spaces of the plurality of hollow fiber membranes, characterized in that: the hollow fiber degassing module further comprises an outer support having a plurality of openings formed therein and disposed between the hollow fiber membrane bundle and the housing; the first sealing portion fixes one support end portion of the outer support to the housing; and the second sealing portion fixes the other support end portion of the outer support to the housing. a hollow fiber membrane bundle including a plurality of hollow fiber membranes bundled into a cylindrical shape; a housing that houses the hollow fiber membrane bundle, includes a liquid supply port and a liquid discharge port that are formed in communication with spaces between the plurality of hollow fiber membranes, and further includes a suction port formed in communication with inner spaces of the plurality of hollow fiber membranes; a first sealing portion that fixes one membrane bundle end portion of the hollow fiber membrane bundle; and a second sealing portion that fixes the other membrane bundle end portion of the hollow fiber membrane bundle, wherein: in a cross section passing through the one membrane bundle end portion and orthogonal to an axial direction of the housing, the first sealing portion fills an entire region in the housing except for a hollow portion of the hollow fiber membrane bundle to form a communication port that serves as an opening of the hollow portion and allows communication between the hollow portion and the liquid supply port; and in a cross section passing through the other membrane bundle end portion and orthogonal to the axial direction of the housing, the second sealing portion fills an entire region in the housing except for the inner spaces of the plurality of hollow fiber membranes, characterized in that: the hollow fiber degassing module further comprises an outer support having a plurality of openings formed therein and disposed between the hollow fiber membrane bundle and the housing; the first sealing portion fixes one support end portion of the outer support to the housing; and the second sealing portion fixes the other support end portion of the outer support to the housing. in a cross section passing through the one membrane bundle end portion and orthogonal to an axial direction of the housing, the first sealing portion fills an entire region in the housing except for a hollow portion of the hollow fiber membrane bundle to form a communication port that serves as an opening of the hollow portion and allows communication between the hollow portion and the liquid supply port; and in a cross section passing through the other membrane bundle end portion and orthogonal to the axial direction of the housing, the second sealing portion fills an entire region in the housing except for the inner spaces of the plurality of hollow fiber membranes, characterized in that: the hollow fiber degassing module further comprises an outer support having a plurality of openings formed therein and disposed between the hollow fiber membrane bundle and the housing; the first sealing portion fixes one support end portion of the outer support to the housing; and the second sealing portion fixes the other support end portion of the outer support to the housing. the hollow fiber degassing module further comprises an outer support having a plurality of openings formed therein and disposed between the hollow fiber membrane bundle and the housing; the first sealing portion fixes one support end portion of the outer support to the housing; and the second sealing portion fixes the other support end portion of the outer support to the housing.