A multi-gap discharge experiment device comprises a multi-gap gas simulation system, an ultraviolet light signal collection system and a voltage and current measurement system. The multi-gap gas simulation system comprises a low-voltage electrode, a potential floating conductor and a high-voltage electrode which are arranged at intervals in order along a straight line, and a testing voltage is connected between the low-voltage electrode and the high-voltage electrode; the ultraviolet light signal collection system is configured to collect ultraviolet light signals in discharge gaps formed by the low-voltage electrode, the potential floating conductor and the high-voltage electrode; and the voltage and current measurement system is configured to measure voltages to earth of the low-voltageelectrode, the potential floating conductor and the high-voltage electrode and current signals of the high-voltage electrode and the low-voltage electrode. The multi-gap discharge experiment device performs analysis and comparison of light signals generated by the multi-gap gas simulation system and the potential and the current of each electrode to determine a multi-gap discharge breakdown voltage level and an energy changing condition of a discharging process, and therefore, the multi-gap discharge experiment device can provide a technical support for research of the multi-gap gas discharge.