The invention relates to the field of sewage treatment, and discloses a method for treating waste water containing ammonium salts. The method comprises the following steps: introducing waste water into each evaporator of a multi-effect evaporation device for evaporation to obtain ammonia-containing steam and a concentrated solution, wherein before the waste water is introduced into the multi-effect evaporation device, the pH value of the waste water is regulated to be more than 9; and sending the ammonia-containing steam obtained through the evaporation of a former evaporator into a latter evaporator to carry out heat exchange with the waste water to obtain ammonia water. The invention provides the low-cost and environment-friendly method for treating the ammonium-containing high-salt waste water. The method can be used to recycle ammonium and salts in the waste water, resources in the waste water can be reused to a largest extent, and near zero emission can be realized.