The ventilation member of the present invention includes: a support; and an air-permeable membrane disposed on the support. The support includes: a base portion supporting the air-permeable membrane; and a leg portion extending from the base portion toward the interior space of a housing and adapted to fix the ventilation member to the opening of the housing. The leg portion includes: insertion portions separated from each other in a circumferential direction by slits formed between the insertion portions in an insertion start side of the leg portion, the insertion portions being adapted to be elastically deformed radially inwardly when the insertion portions are inserted into the opening and then to be fixed to the opening; and receding portions in the insertion portions. In a region between an edge of an inner circumferential surface of the insertion portion and an edge of an outer circumferential surface of the insertion portion at a root of the insertion portion, the receding portion recedes from an imaginary circumferential end surface in a direction away from the slit and recedes from an imaginary inner circumferential surface toward the outer circumferential surface, when the imaginary circumferential end surface is defined as an imaginary end surface including a central axis of the support and a first reference line parallel to the central axis and passing through the edge of the outer circumferential surface and the imaginary inner circumferential surface is defined as an imaginary surface extending in the circumferential direction from the edge of the inner circumferential surface toward the slit.