The invention discloses a capacitance voltage-division device for linearity calibration of an impact voltage divider. The capacitance voltage-division device comprises a first voltage sharing ring anda second voltage sharing ring which are arranged in parallel, wherein an accommodating hole is formed in the second voltage sharing ring, a low-voltage electrode is placed in the accommodating hole,a high-voltage capacitor is formed between the first voltage sharing ring and the low-voltage electrode, a shielding capacitor is formed between the first voltage sharing ring and the second voltage sharing ring, a low-voltage arm is connected to the bottom of the low-voltage electrode, an insulation cylinder is further connected to the bottom of the low-voltage electrode, the low-voltage arm is arranged in the insulation cylinder and is further connected with a computer by a data acquisition device, a distance measurement hole is formed in the second voltage sharing hole, an insulation support rod is arranged at the bottom of the second voltage sharing rod, and a hanging ring is arranged on the first voltage sharing ring. By the capacitance voltage-division device, the high-voltage capacitor is difficult to affect by an external environment, corona and external stray capacitance, the linearity calibration accuracy is favorably ensured, the difficulty in adjusting waveform of an impactvoltage generator cannot be caused, and the measurement range is relatively wide.