Garenoxacin is a type of fluoroquinolone antibacterial agents. Previous studies have suggested that garenoxacin 400 mg once daily dose is appropriate for patients with normal to moderate renal disfunction against common bacteria of respiratory infections. However, limited information has been obtained in terms of treatment for severe renal failure patients, such as hemodialysis patients, with this drug. Twenty severe renal failure patients with respiratory infection received single garenoxacin dose (200 mg and 400 mg). By measuring blood concentration of garenoxacin, pharmacodynamics parameters, such as the peak plasma concentration (C(max)) and the area under the concentration curve (AUC), were calculated with NONMEM. After single dose of garenoxacin, C(max) at the 200 and 400 mg doses were within the range of 2.9 ± 0.6 and 6.0 ± 1.0 μg/mL, respectively. The corresponding values for AUC at the 200 and 400 mg doses were within the ranges of 62.3 ± 11.9 and 128.0 ± 12.5 μg x hr/mL, respectively. The mean half-life (T½) for garenoxacin appeared to be independent of dose (13.9 ± 2.2hr and 13.7 ± 1.9 hr at the 200 and 400 mg dose). There were no serious adverse events suspected to be related with garenoxacin. Consequently, for severe renal failure patients, the 400 mg once daily garenoxacin dose was expected to be effective against common bacteria of respiratory infections.