In a UV high-power radiator, a plurality of dielectric tubes (6) having internal electrodes (7) are disposed in the interior of a quartz housing having rectangular cross section. The interior of the housing is filled with a filling gas which emits UV radiation under discharge conditions. The electrical supply is provided in such a way that the discharges (17) develop between adjacent dielectric tubes (6). A notable feature of this construction is its compactness, economical nature and service friendliness.