We attempted in the present study to clarify the preventive effects of cyclohexenonic long-chain fatty alcohol on ischemia-reperfusion injury in the rat bladder. Rat bladders were exposed to 30 min of ischemia and a subsequent 30 min of reperfusion with or without several doses of cyclohexenonic long-chain fatty alcohol (0.5, 2, 8 mg/kg). Muscle-bath studies were performed, and malonaldehyde concentrations were measured in the bladder. Bladder dysfunction and lipid peroxidation caused by ischemia-reperfusion were prevented by cyclohexenonic long-chain fatty alcohol in a dose-dependent manner. Our data indicate that cyclohexenonic long-chain fatty alcohol can prevent the production of free radicals and ischemia-reperfusion injury in the bladder.