To provide a new permeable carrier fixture facilitating attachment of a permeable carrier carrying material producing at least one of chemical and physical change on air introduced in an internal combustion engine.

The permeable carrier fixture (9) includes a holding member (29) holding the permeable carrier in an intake pipe (5) of the internal combustion engine so that air passes through the permeable carrier (7). The retention member has a style allowing passage of air, gives elasticity on an inner wall (39) of the intake pipe, and can lock the intake pipe thereby.