An all-solid-state LC-Marx generator based on magnetic switch has been proposed and analyzed by theory, simulation and experiment. This system is controlled by 1 MOSFET and magnetic switches that are made by 1 magnetic core. It has dimensions of 130 mm (diameter) and 60 mm (height), which almost not change with the stage increase. The capacitors could be charged to 1.82 times source voltage according to the principle of resonant charging. Five-stage LC-Marx generator could obtain a peak output voltage of -10.9 kV with rise time of 80 ns when the source voltage of 950 V is applied, and the energy efficiency is 30.43% on 500 Ω. The generator has been tested under 30 kHz that could work steadily. It could output higher voltage when used for atmospheric discharge.