Abstract: A voltage stabilizing system of a switching direct current (DC) power supply equipment is provided. DC power outputted by battery modules and a rectifier is boosted, bucked, or boosted and bucked by a voltage stabilizer circuit, and is then distributed to a plurality of external electronic devices or the battery modules. The voltage stabilizer circuit includes a main voltage stabilizer circuit and one or more slave voltage stabilizer circuits. The main voltage stabilizer circuit controls the slave voltage stabilizer circuits, and distributes the DC power respectively to the main voltage stabilizer circuit and the slave voltage stabilizer circuits. Circuit boards of the main voltage stabilizer circuit and the slave voltage stabilizer circuits are pluggably installed in a machine cabinet of the switching direct current power supply equipment.