In order to carry out the measurement of high voltage standard capacitor, a experimental platform was developed. A high voltage capacitor installed on the platform could be titled and rotated at high voltage. The levelness of the test ground, the electromagnetic disturbance induced along the low-voltage lead cable, and the traction of the high-voltage lead wire, may all induce nonnegligible influence in the precise measurement of high voltage standard capacitor. The solution to the above-mentioned influence factors had been put forward in this paper. Furthermore, the influence of the test ground levelness to the capacitance change of high voltage capacitor, had been quantitatively analyzed. This work reduced the uncertainty of the precise measurement on high voltage standard capacitor, and it also provided an important support to the performance evaluation of high voltage standard capacitor.