The invention provides an insulator equivalent salt density prediction model introducing an air quality index. The insulator equivalent salt density prediction model is characterized in that the following steps are provided: utilizing an integration equation to carry out parameter dynamic processing on a classic prediction model; introducing the air quality index which is used as a driving factor for carrying out dynamic estimation on a pollution accumulation rate [Tau], and stressing the dynamic relation between the pollution accumulation rate and the air pollution degree; and adopting a simulation annealing algorithm to carry out global optimal estimation on model parameters, establishing the high-precision equivalent salt density prediction model, and realizing more precise and stable prediction of the equivalent salt density. Considering the easy availability and the wide coverage of air quality index data, the model provided by the invention is hopeful for substantially reducing the cost of area pollution assessment.