The invention discloses an equipment backup method, which is applied to a network system. The equipment backup method adopts a proposal that the equipment backup method comprises: establishing a corresponding relation between the failure number of various types of master equipment and the number of standby equipment, and calculating the failure number in the same type of master equipment; finding out the number of the standby equipment from the corresponding relation according to the failure number of the master equipment, determining the final number of the standby equipment according to the number of the standby equipment, and configuring the standby equipment for the same type of master equipment according to the final number; and selecting the same number of standby equipment from corresponding standby equipment according to the number of master equipment required for backup to replace the master equipment to execute services under the condition of backup of the master equipment. The equipment backup method reduces the construction cost and fund occupation of standby systems under the condition of guaranteeing normal operation of a network system. The invention also discloses an equipment backup device.