The invention relates to a piezoelectric transformer having a piezoelectric element (1) of the length L, wherein an input voltage Uin can be applied on an input side (2) for being transformed into an output voltage Uout on the output side (3) according to a transformation ratio Uout/Uin=Ku. The piezoelectric element (1) comprises multiple plies (4a, 4b, 4c) of inner electrodes, which are arranged in multiple different layers (S1, S2, S3). Each ply (4a, 4b, 4c) of inner electrodes extends along at least one predetermined sub-section of a predetermined length, wherein sub-sections of plies (4a, 4c) of a first group of layers (S1, S3) and sub-sections of plies (4b) of a second group of layers (S2) have different dimensions, so that the piezoelectric transformer satisfies the following condition: Cin≤N2Cout, wherein Cin indicates the input capacitance, Cout indicates the output capacitance, and N indicates the transformation ratio of the ideal transformer.