The invention relates to a configuration method for on-load capacity regulating power distribution transformers, in particular to a configuration method for capacity regulating and value fixing of an on-load capacity regulating power distribution transformer. The method includes the steps of obtaining technical performance parameters of an on-load capacity regulating power distribution transformer; determining a load rate of the on-load capacity regulating power distribution transformer in a large rated capacity operation mode; determining operation consumption of the on-load capacity regulating power distribution transformer; determining a critical load rate; determining a low voltage side current set value of the on-load capacity regulating power distribution transformer; and determining whether the technical performance parameters of the on-load capacity regulating power distribution transformer are changed. According to the configuration method for capacity regulating and value fixing of the regulated capacity distribution transformer, by the analysis and calculation of the technical performance parameters of the on-load capacity regulating power distribution transformer, the capacity regulating and value fixing configuration scheme of the on-load capacity regulating power distribution transformer from a small rated capacity mode to a large rated capacity operation is determined, and the purpose of reducing transformer operation consumption and economic operation is achieved.