The invention relates to a method for controlling the chemical water treatment process of a boiler. The method comprises the following steps: performing efficient fiber filtered-water treatment to remove suspended matters in boiler water; performing cation exchange water treatment to remove cations in the boiler water; performing anion exchange water treatment to remove anions in the boiler water; performing mixed-ion exchange water treatment, wherein each treatment of the water treatment comprises multiple step sequences which are sequentially performed; according to one mode of a time automatic-control mode, a parameter automatic-control mode and an operator manual-control mode, controlling each performance in the efficient fiber filtered-water treatment, the cation exchange water treatment, the anion exchange water treatment and the mixed-ion exchange water treatment; under the time automatic-control mode, controlling the performance of the step sequences according to the set time; under the parameter automatic-control mode, controlling the performance of the step sequences according to the set time and preset parameters; and under the operator manual-control mode, controlling the performance of the step sequences according to the input of an operator.