Abstract: 【Purpose/significance】The complex features of major emergencies and public cognitive processes in the context of cyberphysical-social ternary space are organically combined to build a public cognitive construction model, which provides new ideas for in⁃ cident response, helps to solve complex problems in a synergistic manner, and thus improves the overall emergency response level of the society.【Method/process】By integrating relevant theories of psychology and intelligence, we analyze the constructive relationship between the cognitive subject and the event from the perspectives of cognitive perspective and meaning construction, clarify the inter⁃ nal and external driving force of cognitive construction, outline the logical process and results of cognitive construction, and present the internal mechanism of public cognitive construction in major emergencies.【Result/conclusion】This paper proposes to mobilize the public′s subjective initiative and maintain the objectivity and comprehensiveness of the constructed results, and provide custom⁃ ized intelligence generation and recommendation services for the public, so as to assist the public in acquiring effective intelligence and completing the cognitive leap from concrete phenomena to abstract laws.【Innovation/limitation】This research lays a theoretical foundation for the future rational use of public cognitive characteristics to deal with major emergencies, and needs to be further supple⁃ mented and improved in terms of actual case proving.