The usefulness of navigation systems for revision total hip arthroplasty (THA) remains unclear. The purpose of this study was to evaluate the accuracy of cup positioning using a navigation system in revision THA. Cup alignment of thirty revision cases was evaluated. Data were also compared with those of 30 navigated primary THA cases. In the revision THA group, mean difference in postoperative measurement from preoperative plan was 0.5±4° (range, −9° to 8°) for inclination and −0.07°±5° (−14° to 13°) for anteversion. Mean difference in postoperative measurement from intraoperative record was 0.7°±3° (−5° to 8°) for inclination and −0.7°±3° (−12° to 5°) for anteversion. Compared with the primary THA group, none of these parameters were significantly different. This navigation system was useful even in revision THA.