The invention belongs to the technical field of computer network information security control, and discloses a computer network information security control system and method. The computer network information security control system comprises a network information acquisition module, a network information transmission module, a main control module, a network information identification module, an encryption module, an intrusion detection module, an alarm module, a cloud storage module and a display module. After the information to be forwarded is received through the network information transmission module, the information to be forwarded is forwarded to a next-level information receiver, so that in the multi-stage transmission process of the information, each stage of information receivercan acquire the source of the information, the transmission path of the information and the relationship between the information sender and the information receiver in each stage, at the same time, whether the to-be-identified network information is credible or not can be determined through the network information identification module background, that is, whether the to-be-identified network information is credible or not is determined by utilizing the similarity, and accordingly the rumor can be automatically and effectively identified.