The invention discloses a direct-current (DC) power supply for guaranteeing fully stored energy of stored energy motors of a breaker and a load switch, which is characterized in that an alternating-current (AC) input filter circuit is connected with a constant-current charging circuit and an stored energy circuit in series; one line at an output end of the stored energy circuit is sequentially connected with a DC/DC convertor, a sampling resistor R1, a switching key K1 and a spring operating mechanism in series; and the other line at the output end of the stored energy circuit is connected with a first input end A1 of a detection and control circuit, a second input end A2 of the detection and control circuit is connected with an output end of an output current sampling circuit, the output current sampling circuit is connected with the two ends of the sampling resistor R1 in parallel, a first output end B1 of the detection and control circuit is connected with the DC/DC convertor, and a second output end B2 of the detection and control circuit is connected with a monitoring device. The DC power supply has the beneficial effect that the detection and control circuit and the output sampling circuit control the DC/DC convertor, thus restraining the problem that the spring operating mechanism in the breaker or load switch is not in place due to insufficient power supply energy, thereby reducing accident occurrence, and meeting operational needs of the spring operating mechanism.