A magnetic force microscope capable of producing a topographic image containing no magnetic information. In the topographic imaging mode, an error amplifier controls the distance between a cantilever and the sample to cause the oscillation frequency of the cantilever to shift from f0 to f1, for causing a probe to tap each observation position (xi, yj) on the sample. According to the results of the control, topographic information in the observation position (xi, yj) is obtained. In the magnetic force imaging mode, the probe is placed on the observation position (xi, yj), and the distance between the cantilever and the sample is held to the distance used in the topographic imaging mode according to information stored in the memory. At this time, the amplitude of the cantilever is so adjusted that the probe does not tap the sample. Magnetic information about the observation position (xi, yj) on the sample is obtained based on the oscillation frequency of the cantilever at this time.