In order to meet the need of magnitude transmission of high voltage pulse amplitude, this paper develops the design of high voltage pulse amplitude calibration device with pulse amplitude of 1-20 kV and pulse width of 1-100 μs. The calibration device takes the high voltage MOSFET as the core, and builds up a multi-stage Marx structure to achieve high voltage pulse. At the same time, the truncation circuit greatly reduces the pulse fall time and realizes the output of rectangular pulse waveform. On the basis of the Marx structure, the unit is built as a whole. The pulse width and amplitude can be adjusted by triggering pulse and high voltage DC power supply voltage, and the high voltage isolation is guaranteed by isolating power module and optical signal. The device uses high-precision high voltage probe and oscilloscope to constitute the internal measurement module. The measurement value is the standard value of the calibration device. The uncertainty of the pulse amplitude of the device is evaluated, and it is verified by comparison of two measurement standards. The calibration device is tested with other types of high voltage probes. The results show that, compared with the low-voltage pulse calibration source, the high voltage pulse can effectively characterize the performance and measurement accuracy of the high voltage probe, achieve the calibration of the high voltage probe, and the device can also be applied as a high voltage pulse source for other purposes in the field of pulse power field.