A sound-absorbing panel includes: an inner skin traversed by holes and intended to be oriented towards a channel in which a fluid flows, a heating mat formed by strips fixed to the inner skin on the side opposite to the channel and oriented in a first direction, wherein two adjacent strips are distant from each other in order to define a slot between them, a base fixed to the strips on the side opposite to the inner skin, wherein the base includes, on the strips side, grooves extending in a second direction different from the first direction and wherein the base has, between two successive grooves, a rib, a cellular core fixed to the base on the side opposite to the strips, and an outer panel fixed to the cellular core on the side opposite to the base.