Many applications including plasma excitation and high-power microwave sources require miniaturized high-voltage pulse generators. A miniaturized Marx generator with a novel magnetic isolated drive circuit is proposed. Making the source terminals of the charging MOSFET and discharging MOSFET in adjacent stages shorted in Marx generators based on half-bridge circuits, we apply a bipolar signal to both gates of these two MOSFETs and control both their switching. Combined with magnetic isolated driver with primary windings in series, only one bipolar signal from the primary side can synchronously drive all switches in the Marx generator, which considerably reduces the number of required components in the drive circuits. A 14-level experimental prototype was built, with a total weight of only 314 g, a width of 15 cm, a length of 8 cm, and a height of 5 cm. High-voltage square wave pulses with a peak voltage of 10 kV, a repetition frequency of 10 kHz, and a pulse width ranging from 200 ns to 5 μs were obtained over a resistive load. The 500 ns, 10 kV, and 1 kHz square wave pulses generated by the prototype were used to drive the dielectric barrier discharge load, and a uniform and strong discharge was generated, indicating that the miniaturized Marx generator is suitable for driving the dielectric barrier discharge load and being used as a low-temperature plasma source.