A combustion chamber pressure sensor is provided for recording a pressure in a combustion chamber of an internal combustion engine, the combustion chamber pressure sensor has a housing having an inner space that is at least partially enclosed by the housing. At least one mechanical-electrical transducer element, for recording the pressure, is accommodated in the housing. The housing has at least one housing opening. The housing opening is sealed by at least one diaphragm. The diaphragm has at least one convex curvature towards the inner space.