A current regulation method of multiple beams includes acquiring a current density distribution; selecting at least one beam whose current density is equal to or more than a threshold; measuring a current value of the at least one beam respectively by varying a voltage applied to the Wehnelt electrode and acquiring a correlation between the voltage and the current value; moving a stage to a position where the at least one beam is allowed to enter a current detector each time writing of a stripe region is completed; measuring, after moving the stage, a current value of the at least one beam while beams of the multiple beams whose current density is less than the threshold are blocked; operating a target voltage value applied to the Wehnelt electrode to cause the current value measured to be a target current value; and applying the target voltage value to the Wehnelt electrode.