The iron minerals in the tailings of a gold cyanidation process are various in kinds and magnetism and in fine grains so that weak magnetic and strong magnetic separation in turn doesn’t achieve satisfactory index.The paper chose alternating weak magnetic and strong magnetic separation to carry out iron practical experiment and optimized the experimental conditions.Under the optimal conditions,the TFe grade of the magnetite concentrate obtained is 62.43 %,the recovery rate is 21.62 %,productivity is 12.54 %,the TFe grade of the limonite concentrate obtained is 50.51 %,the recovery rate is 21.36 %,productivity is 15.31 %.The process has reasonable distribution of magnetite and limonite,further improving comprehensive economic profits.