The invention provides a preparation method of sulfur free-cutting stainless steel. The preparation method comprises the steps that alloy raw materials are sequentially subjected to EF smelting, AOD smelting and LF smelting to obtain alloy liquid; the alloy liquid is subjected to die casting to obtain a cast ingot; and the cast ingot is subjected to cogging and then is rolled, and the sulfur free-cutting stainless steel is obtained. By adopting a novel process technological route of electric furnace, AOD, LF and die casting, on the basis that chemical components meet the requirements, the lownitrogen content is controlled through AOD smelting, the nitrogen content is controlled to be less than 200 ppm so as to improve cold-hot plasticity and finished product plasticity of materials, and the hot machining yield and the performance comprehensive index of the materials are effectively increased. The invention further provides the sulfur free-cutting stainless steel.