Temporal ventriloquism refers to the phenomenon that a sound presented in close temporal proximity of a visual stimulus attracts its perceived temporal occurrence. Here, we investigate the time-course of the neuronal processes underlying temporal ventriloquism, using event-related brain potentials. To measure shifts in perceived temporal visual occurrence, we used a paradigm in which a sound modulates the magnitude of a visual illusion called the flash–lag effect. A sound presented before the flash reduced both the size of the flash–lag effect and the amplitude of visual N1 compared with when the sound lagged the flash. We attribute the modulation of the flash–lag effect to a modulation of facilitation of visual processing. The time-course (190 ms) and localization (occipitoparietal cortex) of this particular auditory–visual interaction confirms the sensory nature of temporal ventriloquism.