There is described a unit for sterilizing container closures comprising: a process chamber having an inlet for receiving a succession of closures to be sterilized and an outlet from which sterilized closures exit conveying means for advancing the closures through the process chamber along a predetermined path (P) and radiation emitting means acting inside the process chamber, facing the closures moving along the above path (P) and which can be activated for directing sterilizing radiations on said closures to sterilize their surfaces the conveying means comprise actuator means acting on each closure to produce a rolling movement thereof while it advances along its path (P).
