The invention relates to a method for checking a direct current charger of a power plant, which is used for checking voltage stabilization precision, current stabilization precision and a ripple factor of the direct current charger and comprises the following steps: calculating the number of modules tested simultaneously according to a whole screen current value of the direct current charger and an output current of a load box; converting a current signal into a voltage signal through a series current divider, indirectly obtaining an output current and an output voltage of the direct current charger through observing the change of a voltage value, and judging the voltage stabilization precision and the current stabilization precision according to related regulations; and reading a peak-to-peak value under the corresponding voltage value by an external oscilloscope method, and further calculating the ripple factor. The method of the invention has the beneficial effects that: the load box is used for operation, thus simple operation and high accuracy are achieved; through checking of a plurality of modules or the whole screen, the overall working state of the charger can be reflectedvisually, visual data are provided for operation of equipment, at the same time, test time is greatly reduced, and a working efficiency is improved.