Abstract: A method of treatment of liquid, air and surfaces using UV radiation with a pulse duration of 10−6 to 10−3 sec. and a radiation intensity of at least 100 kWt/m2, using a plasma radiation source with a pulsed storage element, wherein the energy stored in the storage element at the time of discharge, the pulse duration and the area of the radiating surface of the radiation source are interrelated as follows: W0/A Srad t ½>1, where W0, is the energy stored in the storage element, Joules; Srad is the area of the radiating surface of the radiation source, m2; t½ is the radiation pulse duration at mid-height of a peak, sec.; A=108 Wt/m2 is the constant coefficient. A device for the UV treatment of liquid, air and surfaces includes a secondary winding integrated in a series with a charged condenser, and a pulsed lamp to form a discharging circuit.