The invention aims to solve the problem that a fault simulation experiment apparatus of an SF6 gas insulated electric appliance in the prior art cannot effectively stimulate the faults such as spark discharge, and provides a gas insulated substation spark discharge fault simulation experiment apparatus and a method thereof. The experiment apparatus includes a basic circuit, a relay control circuit, an SF6 discharge device, an energy detection device, and a defect device. The experiment apparatus and the method make up the defect that spark discharge times cannot be controlled under alternating current, so that the fault determination accuracy of the SF6 gas insulated electric appliance is improved, the voltage and current information of the spark discharge can be acquired in real time to obtain the spark discharge energy through calculation to enrich the quantitative criteria of the fault degree of the SF6 gas insulated electric appliance. The experiment apparatus and the method realize the effective control of spark discharge times and frequencies and guarantee the stimulation accuracy.