PURPOSE: To provide a semiconductor device testing device the testing time of which can be shortened.

CONSTITUTION: Output voltage value measured data are stored in a measured data storing RAM 2 in the order of output terminal numbers and, when output data are accumulated by one hierarchy, the maximum value, minimum value, and mean value of the output data are calculated. Then the calculated maximum, minimum, and mean values are respectively stored in maximum, minimum, and mean value storing sections 4, 5, and 6 and respectively compared with reference values. Since the output voltage in another hierarchy can be measured and the measured data can be stored in the RAM 2 in parallel with the calculation of the maximum, minimum, and mean values, the testing time of a semiconductor testing device can be shortened.