Little is known about doses and onset times of rocuronium after sugammadex reversal. We report a 2-year-old girl receiving readministration of rocuronium for reoperation 30 minutes after sugammadex reversal. The patient underwent ventriculoperitoneal shunting for hydrocephalus under general anesthesia with muscle relaxation by rocuronium. After completion of surgery, muscle relaxation was antagonized by sugammadex 4 mg x kg(-1). Thirty minutes after extubation, reintubation and readministration of rocuronium were required for additional surgery. Rocuronium was administered again under monitoring of muscle relaxation. As the efficacy of rocuronium was definitively reduced, a higher dose (2 mg x kg(-1)) and a longer onset time (6 minutes) were required to establish maximal block (T1 0%). There were no apparent problems with the clinical duration of rocuronium or repetitive antagonization by sugammadex. Under appropriate monitoring, repetitive muscular relaxation by rocuronium can be safely established.