A method for protecting a Digital Subscriber Line Access Multiplexer (DSLAM) includes: capturing specific protocol packets at an XDSL port by hardware of an XDSL single service board; and sending the captured specific protocol packets to a CPU of the XDSL single service board; determining whether the traffic amount of the specific protocol packets in a time unit exceeds a predefined threshold, if the traffic amount does not exceed the predefined threshold, submitting the specific protocol packets to a CPU of the host; otherwise stopping submitting the specific protocol packets to the CPU of the host. The method and the XDSL single service board provided by embodiments of the present invention need not manually set Media Access Control (MAC) address or maximum MAC address learning number for each XDSL port, which cuts down the maintenance workload, and on the other hand, reduces the loss of important protocol packets and lowers the load of the CPU.