The present invention relates to a voltage measuring device for correcting a voltage error using the correction table recorded with a plurality of correction values. The present invention is a digital analog converter to equal parts the digital value of the internal voltage from the correction mode to the plurality of outputs as an analog value, calculating an analog correction value for the internal voltage, and a digital value of the digital correction corresponding to the output analog correction values, respectively value of the analog to the correction value store a correction value comprises a correction value calculation unit for generating a correction table, the correction table is stored which is the storage unit, when connected to an external device for measuring the digital value for a specific voltage of the external device analog to digital conversion unit, through the index setting unit and the index is set calculation for setting the index of a predefined calculation formula based on a measured and a plurality of the correction value of the digital correction value recording digital values ​​in the correction table, the specified voltage of the external apparatus includes a voltage obtaining part obtaining.