Steel with low content of tiny inclusions and preparation method thereof

The invention particularly relates to steel with low tiny inclusion content and a preparation method thereof, and belongs to the technical field of steel preparation. The method comprises the steps that molten iron is subjected to converter smelting, and converter molten steel is obtained; the converter molten steel is refined; refined molten steel is obtained; continuously casting the refined molten steel to obtain a steel billet; refining slag is added in the tapping process of converter smelting, the refining slag comprises lime, and the using amount of the lime meets the set amount so that the CaO/Al2O3 ratio of the slag can be increased; adsorption and removal of inclusions are promoted by controlling the adding amount of the lime and increasing the ratio of CaO to Al2O3 in the slag, removal of the tiny inclusions is enhanced, and the problem that the content of the tiny inclusions in current steel is large is solved. 本发明特别涉及一种微小夹杂物含量少的钢材及其制备方法，属于钢材制备技术领域，方法包括：对铁水进行转炉冶炼，得到转炉钢水；对所述转炉钢水进行精炼；得到精炼钢水；对所述精炼钢水进