The invention discloses a discharging current measuring device of a rod-plate structure based on an insulated area combination method, and belongs to the technical field of corona discharge measurement. An anode plate is divided into concentric circle areas, and the areas are separated from each other via an insulating material; and the lower of each insulated area is grounded via a non-inductive resistor, and a voltage of the resistor is connected to an oscilloscope via a matched coaxial cable. According to the invention, distribution characteristics of spatial corona current can be analyzed, and the condition that simulation waveform cannot match experimental waveform can be explained effectively.