The invention relates to a system for generating ultra-short electromagnetic pulses with rise time of less than 1 ns, duration in the range of nanoseconds and repetition frequency in the range of tens of kHz. According to the invention, the system consists of a discharge tube (1) made of ceramic material, provided with two metallic pointlike electrodes (2, 3), wherethrough a gas stream of optimized speed circulates, the two electrodes (2, 3) being connected to the output of a high-voltage pulse transformer (6) by means of an adaptive capacitive circuit (9), between which electrical discharges of high repetition frequency, in the range of tens of kHz, take place, where the system may be used for developing, testing and calibrating diagnostic and screening equipments, and attenuation of intense electromagnetic pulses associated to the interaction of high-intensity laser pulses with powers in the range of PW, with various types of targets, by generating pulses having the same wave shape and the same temporal characteristics.