A magnetic field measuring method using a magnetoelectric composite element as an oscillator, in which a time-dependent measurement magnetic field acts on the magnetostrictive phase of the composite element, and an electrical measurement voltage is tapped off across the piezoelectric phase of the composite element and is used to infer the measurement magnetic field. At least one dielectric phase is connected to the magnetostrictive phase of the composite element by a material bond. When an electrical voltage is applied, the dielectric phase exhibits a change in length, the magnitude of which depends in a non-linear manner on the magnitude of the voltage, and a temporally periodic electrical modulation voltage is applied to the dielectric phase.