Abstract: The paper presents a 500 kV all-solid-state Marx generator adopting Z type circuit. In this Marx generator, twenty-eight isolated gate bipolar transistors(IGBTs) serial modules were utilized as controllable switches. The maximum working voltage of each IGBTs module was designed as high as 22 kV, and the repetition rate at full load condition was designed as high as 200 Hz. The ladder type pulse-forming-networks (PFNs) consisting of metallized film capacitors and wound inductors were designed as energy storage and pulse-forming components. Experimental results indicate that the Marx generator can run with 500 kV output pulses and 50 Hz repetition rate in burst-mode successfully. The peak output pulse voltage of this generator is approximately the same as that of the highest power solid-state Marx generator ever reported, while the peak current is almost twice, reaching 1 000 A. The maximum pulsed power of the generator is as high as 500 MW. As the capacitors were utilized as energy storage components, the pulse width can be adjusted from 3 s to 10 s continuously.