To provide a potential treatment apparatus capable of inhibiting a variation in effects on a living body even when a setting of direct current voltage composition is changed after voltage has set. This potential treatment apparatus 1 comprises a first voltage setting input means 2 to input the setting of voltage effective value Erms, a second voltage setting input means 3 to input the setting on a scale of direct current voltage with a minus-shift MS, a voltage component calculating means 5 to calculate alternate current voltage component Eac and direct current voltage component Edc of an output voltage so that effective value of the output voltage cannot be far from the voltage effective value Erms inputted by the first voltage setting input means 2 based on the settings inputted by the first and second voltage setting input means, a high-voltage output means 6 to output the voltage which is the combination of the calculated alternate current voltage component Eac with the direct current voltage component Edc as an output voltage, and an output terminal 7.
