A novel indoor mobile 7200kV impulse voltage generator is provided with main capacitors, wherein insulating stand columns are arranged beside the main capacitors, the main capacitors are hung on the insulating stand columns externally, the main capacitors are distributed in a V shape beside the insulating stand columns, wave modulating elements arranged beside the insulating stand columns, insulating ladders are arranged between the insulating stand columns and the wave modulating elements, the wave modulating elements are connected with each other in series, and a multiple-electrode ignition device is arranged beside the wave modulating elements. The novel indoor mobile 7200kV impulse voltage generator is compact in structure, the inductance is small, the wave modulating elements are of a pairwise-serially-connected structure, so that the wave modulation ranges of the wave modulating elements are wide, a tower-shaped building block type structure is adopted, the installation is convenient, the insulating ladders and insulating platform are arranged and can bring convenience for the debugging personnel to climb and maintain, the bottom part of the impulse voltage generator is provided with air cushions which can facilitate the impulse voltage generator to move back and forth, the provided multiple-electrode ignition device makes the ignition effect good, and the adjustment is convenient.