The invention relates to the technical field of network security, and relates to a method and system for detecting an interest packet flooding attack in a content center network. The method comprisesthe following steps: counting a probability distribution model of a content name prefix of an interest packet; calculating an information entropy of a router according to a statistical value; and comparing the information entropy with a given threshold, and then calculating an entropy rate. In the interest packet flooding attack detection scheme designed by the invention, the difference between the entropy rate change of the legal burst stream and the attack stream is considered, the outburst stream of a legitimate user and an attack stream of an attacker are effectively distinguished on the premise of ensuring that the attack is detected as soon as possible, thereby effectively reducing the misjudgment of the legitimate user.