To measure surface information and physical information of a sample with high accuracy by promoting linearity in Z direction by nullifying cross talk in XY directions as less as possible, there is provided a surface information measuring apparatus including a probe having a stylus, a Z actuator fixed with the probe for being elongated and contracted in Z direction orthogonal to a sample surface B when applied with a voltage, an applicator for applying the voltage to the Z actuator, and a controller for controlling to operate the applicator, in which the Z actuator includes a piezoelectric member capable of being elongated and contracted in Z direction and a plurality of divided electrodes provided to be respectively electrically independent from each other in a state of being divided by at least 3 or more in a peripheral direction at an inner peripheral face or an outer peripheral face of the piezoelectric member for applying voltages to elongate and contract the piezoelectric member within ranges of contact regions, and the controller controls the applicator to apply voltages by a previously determined rates of voltage applying amounts such that elongating or contracting amounts of respective contact regions of the piezoelectric member respectively brought into contact with the divided electrodes respectively become the same.