To provide EA material and a mounting structure thereof capable of absorbing position error between a projection or the like of a member side such as a trim and a projection insertion hole of EA material.

The EA material 1 has a cylindrical flexible material 10 integrated with an EA material main body 1m formed out of hard urethane foam. A round hole of the cylindrical flexible material 10 is an insertion hole of a projection 4. Even if positions of the projection 4 and the projection insertion hole misalign to some extent when the EA material 1 is mounted on the trim 2, the EA material 1 can be mounted on the trim 2 by making the positions of the projection 4 and the projection insertion hole coincide with each other since the flexible material 10 can be compressed in a direction along a plate surface of the trim 2.