An ultrasonic sensor includes a housing having a peripheral side wall and a base surface, i.e., it is configured as essentially pot-shaped. The base surface is configured as a diaphragm. A transducer element, which is configured as a piezoelectric element, for example, and is used for generating and detecting ultrasonic oscillations, is situated on the base surface. At least one mass element is situated on the base surface so that the resistance of the mass element against an oscillation of the diaphragm increases with rising oscillation frequency.