Although 2% of SiMn addition which was done at once or dividingly decreased the oxygen content to 0. 004%, the desulfurization was not significantly influenced. The addition of calcium complex deoxidizer containing aluminum, after lowering the oxygen content, decreased the sulfur content considerably below that obtained with CaSi, CaSiMn and CaSiBa additions. With a constant oxygen content the amount of sulfur was a minimum in the case of steel deoxidized dividingly with the calcium complex deoxidizer containing aluminum.