The invention relates to a redundancy power supply system which comprises a machine body provided with a first holding part and a second holding part; a first power supplier provided with a first connecting port; a second power supplier provided with a second connecting port; and a power switching circuit board which is arranged in the interior of the machine body and provided with a power switching circuit, a first slot and a second slot, wherein, the first slot is connected with the first connecting port of the first power supplier, and the second slot is connected with the second connectingport of the second power supplier; furthermore, the power switching circuit board is approximately vertical to the length direction of the first power supplier and the second power supplier so that the power switching circuit board is used for switching and outputting the power provided by the first power supplier and/or the second power supplier. The invention can reduce the whole length of theredundancy power supply system and promote heat elimination effect as well as connect the redundancy power supply system with power receiving equipment directly so as to provide power required by thepower receiving equipment.