To further promote the application of solid-state Marx generators, enable them with the visual display of output pulse waveforms, more accurate regulation of voltage, and shorter charging regulation time, it is necessary to study the automatic control of solid-state Marx generator. In this paper, with a field programmable gate array (FPGA) as the controller, the output voltage, frequency, pulse width, overcurrent threshold value, and other parameters, as well as fault detection and indication, are all directly displayed on the LCD screen to realize visible settings and adjustment. In solid-state Marx generators, a voltage dividing circuit in parallel with the output and a high-speed analog-digital conversion circuit is used to realize high-voltage pulse sampling of the output. With these sampled voltage values, on the one hand, the closed-loop segmented PID control can be realized to achieve fast charging and precise adjustment of the output voltage. On the other hand, the basic waveform of the real-time pulses can be displayed in the virtual oscilloscope. Besides, fault detection and protection mechanisms have been added to the circuit to quickly detect over-temperature, overcurrent, and other faults in the circuit and respond to their timely shutdown to protect the pulse generators and the operators. The voltage waveforms of repetitive square pulses generated by the topology of a 20-stage solid-state square Marx generator indicate that the basic automatical control of this solid-state Marx generator has been realized and it can operate reliably.