The invention discloses a method for treating water by using zero-valent iron-nickel bi-metal activated persulfate. According to the method, the zero-valent iron-nickel bi-metal activated persulfate is used, and micropollutants in the water are removed. The zero-valent iron-nickel bi-metal activated persulfate is used for efficiently generating high-oxidizing-property sulphate radical and high-oxidizing-property hydroxyl radical to attack the micropollutants, the micropollutants are degraded, and the purpose of quickly and thoroughly removing various poisonous and harmful micropollutants such as polychlorinated biphenyl, brominated flame retardants, medicines, personal care products (PPCPs) and algal toxin can be achieved. Compared with the existing the method for treating water by using zero-valent iron activated persulfate, the method has the advantages of high activating efficiency, high yield of the sulphate radical, high micropollutants removing efficiency and the like, is convenient and easy to operate, obvious in effect and wide in pH (potential of hydrogen) using range, and can be used for ground water remediation, treatment of industrial water comprising electroplating wastewater, wastewater of hospitals, printing and dyeing wastewater, treatment of drinking water, treatment of sewage and the like.