Methicillin-resistant Staphylococcus aureus (MRSA) is now endemic in many hospitals. Infection with MRSA is more frequent in the intensive care unit (ICU) than in general wards. Therefore, appropriate treatments for MRSA infections will lead to good outcomes in the ICU. Teicoplanin is an anti-MRSA agent. Recently, it was recommended at a new target trough concentration of 15–30 µg/mL. However, the initial loading procedure for teicoplanin to allow it to reach the target concentration promptly remains uncertain. Therefore, this study aimed to determine the appropriate initial loading procedure for teicoplanin in critically ill patients with severe infections. We performed a retrospective study in patients given teicoplanin in the ICU in order to determine the initial loading procedure to promptly reach the target trough concentration. We then evaluated the trough concentration on the third day after commencement of teicoplanin therapy. The mean loading dose and trough concentration were 11.5±1.0 mg/kg and 18.9±5.9 µg/mL, respectively. A correlation ( r =0.45, p =0.046) was shown between teicoplanin loading dose and trough concentration. The correlation equation was trough concentration=2.563·loading dose −10.672. In the cases of 11.0 and 15.0 mg/kg for the loading dose, respectively, trough concentrations were 17.5 and 27.8 µg/mL. We suggested that an initial loading dose of 11–15 mg/kg every 12 h for 3 doses should be administered to promptly achieve the target trough concentration of 15–30 µg/mL on the third day after commencement of teicoplanin therapy in the ICU.