Abstract: A removable interface cushion for a prosthetic limb is adapted to be snugly fitted within a prosthetic limb outer socket over the interconnection components which connect the outer socket to the upright assemblies. The interface cushion is adapted to abut and provide comfort to the wearer's residual limb when the socket is worn on the residual limb, because the interface cushion is formed from an elastomeric material and has a substantially concave proximate surface. The interface cushion also includes a cavity in the distal end of the cushion for receiving the interconnection components; and the mouth of the cavity has an annular projection extending therefrom which is adapted to abut the inner surface of the socket to create an airtight seal between the interface cushion and the inner surface of the socket when the cushion is snugly fitted into the distal end socket cavity.