A micromechanical acoustic sensor element, which has at least one diaphragm and at least one fixed counter element, the diaphragm being situated in a cavity between a substrate and the counter element and acting as movable electrode of a capacitor system, the counter element acting as first fixed counter electrode of this capacitor system, and at least one through hole being formed in the substrate for the application of sound pressure to the diaphragm. For fixation and strengthening purposes, the counter element is connected to the substrate via at least one support element. The support element is situated in the region of the cavity, and an opening is formed in the diaphragm for the support element.