The invention relates to a method for carrying out researches and tries for reactive power automatic arrangement under actual power grid data and provides a reactive power automatic arrangement method based on available resources of reactive power equipment. The method can automatically arrange the input quantity of parallel capacitor-reactors aiming at mode data of the arranged grid structure and parameters, generated output and load size, so as to guarantee voltage to be acceptable and meet reactive power balance. Reactive power arrangement calculation is based on direct-current load flow. In consideration of the actual installation situation of the parallel capacitor-reactors, the existing equipment resources are fully utilized to realize the regional balance of reactive power. The method has the advantages that since reactive power balancing is performed to load flow data, the reactive power reasonability of power grid mode arrangement can be improved, the convergence of the load flow data is improved, the setting of reasonable reactive power configuration is facilitated and the automation of mode arrangement is realized.