In a hearing protection earplug made of foamed material, provision is made in order to attain a defined attenuation and avoid annoyances caused by self-generated sounds, that the surface of the hearing protection earplug has hollows in the area of the inner end face. The hearing protection earplug includes a main body having a central center longitudinal axis and in the direction of this central center longitudinal axis an axially inner end face and an axially outer end face. In the area of the inner end face, surface area enlarging inner hollows are provided, one of which, in the form of an inner central longitudinal hollow, extends inward longitudinally relative to the center longitudinal axis, starting from the inner end face. Also provided is an outer central longitudinal hollow that extends inward longitudinally relative to the center longitudinal axis, starting from the outer end face. The inner and the outer central longitudinal hollow are separated from each other by a continuous transverse wall extending perpendicular to the central center longitudinal axis.