The electromagnetic radiation effect of high-voltage, subnanosecond pulsed electric fields attracts strong interest from researchers because of its significant development potential in biological treatments, particularly in noninvasive diagnosis and treatment. But up to now, high-voltage subnanosecond pulse generators are widely used for national defense and military, and they are difficult to implement successfully in the civil medical field. A compact, self-contained, repetitive frequency, high-voltage subnanosecond pulsed power source is proposed in this paper. It was designed, built, and tested successfully. Based on a four-stage, low-inductance Marx generator, the pulsed source produces subnanosecond rise-time pulses. A chopping switch was designed to cut off unformed signals and generate subnanosecond pulses. A measurement device, based on the principle of a capacitive voltage divider, was also constructed to determine both the amplitude and the rise-time of the pulse delivered by the source. Preliminary tests show that the source can produce repetitive frequency pulses with a peak value that exceeds 30 kV, as well as rise-time and pulse width (full wave at half maximum) within 1 ns under atmospheric pressure conditions. The pulse amplitude may be extended to hundreds of kilovolts by filling the switch system with an inert gas. The rise-time would be shortened as well. The pulsed power source shows optimistic prospects in the biological fields.