The embodiment of the invention provides a dynamic protection method and a dynamic protection device, and relates to the technical field of automatic attack protection. The method comprises the following steps: firstly, receiving a first access request and an IP address sent by a first client and sending the first access request to a server; then, receiving a first feedback information sent by theserver in response to the first access request; judging whether the IP address is consistent with a prestored first secure IP address, if the IP address is not consistent with the prestored first secure IP address, generating a corresponding first messy code information according to the first feedback information; and finally, sending the first messy code information to the first client. The dynamic protection method and the dynamic protection device provided by the invention have the advantage of making hackers cannot attack the server through automated tools.