The invention relates to a method for conducting clean conversion on roasting and cyaniding tailings. The method comprises the steps of first-level acidification for cyanogen removal, first-level dehydration, second-level acidification for cyanogen removal, second-level dehydration, powerful oxidation for cyanogen removal, magnetic separation, waste water treatment and the like. The method has the beneficial effects that cyanogen-containing matter in the roasting and cyaniding tailings is subjected to multi-level segmented acidification and oxidation treatment and multi-level powerful dehydration and desorption treatment, so that the roasting and cyaniding tailings are converted into leaching liquid with the content of the cyanogen-containing matter being lower than 0.45 mg/L in a clean manner, wherein the content of the cyanogen-containing matter is far below that specified in the national solid waste discharging and stockpiling standard.