The present invention provides a method of processing pre-warning on network equipment, comprising first transmitting at least a primary address resolution protocol ARP request packet to the network equipment in a detecting range, receiving an ARP answering packet in scheduled time; storing a mapping relation between Internet protocol IP address of the ARP answering packet and the medium access control (MAC) address satisfying a first judging condition, which at least includes the ARP answering packet is consistent with the number of the ARP request packet; monitoring the ARP data packet which includes the ARP request packet and the ARP answering packet, when satisfying a second judging condition, emitting pre-warning information, wherein the second judging condition at least includes that the source IP address in the ARP data packet and the source MAC address are not consistent with the stored mapping relation. The invention also provides a pre-warning device, network equipment and corresponding storage medium. The present invention generates pre-warning inform when finding illusory ARP answering packet, thereby causing the user timely to be positioned to the equipment with illusory network address.