Ischemia/reperfusion (I/R) injury represents an important cause of bladder contractile dysfunction. One of the major causes leading to this dysfunction is thought to be reactive oxygen species formation. In this study, we investigated the potential benefit of N-acetylcysteine (NAC), a potent antioxidant that neutralizes free radicals, in a rat model of urinary bladder injury. NAC treatment rescues the reduction of contractile response to I/R injury in a dose-dependent manner. In addition, all levels of reactive oxygen species, lipid peroxidation, and NADPH-stimulated superoxide production in the I/R operation + NAC (I/R + NAC) group also decreased compared with a marked increase in the I/R operation + saline (I/R + S) group. Moreover, an in situ fluorohistological approach also showed that NAC reduces the generation of intracellular superoxides enlarged by I/R injury. Together, our findings suggest that NAC has a protective effect against the I/R-induced bladder contractile dysfunction via radical scavenging property. Copyright © 2013 John Wiley & Sons, Ltd.