In order to provide a functional component attaching member of which durability can be further improved because when a load is applied to a functional component while a vehicle is travelling, the load can also be borne by portions other than a wall portion opposite to a load direction, the present invention provides a rubber functional component attaching member (functional component mounting base 1) for fastening a functional component 29 to an inner surface 70 of a tire, comprising a bottom surface 4 that is fixed to the inner surface 70 of the tire, an attaching portion 2 having a recessed portion 2A to which a functional component-side attaching portion 30 provided to the functional component 29 is attached, and a reinforcing material 20 embedded in a rubber portion on an outer side of the recessed portion 2A.