The main purpose of adding lime in Basic Oxygen Furnace (BOF) is to make slag for both desulfurization and dephosphorization. However, it seems paradoxical when producing high-[P] but low-[S] steel, desulfurization is critical but not dephosphorization. This study investigates the effort of reduced lime consumption or desulfurization and dephosphoriztion. This study clarifies the effect of potential of reducing lime consumption on dephosphorization.