This article is an overview of chronic posttraumatic stress disorder incorporating its etiology, treatments, certain controversies, and recommendations for future development. Based on the diagnostic criteria of DSM-5 and ICD-10 and the research and summary of previous literature. This paper summarizes the etiology of chronic posttraumatic stress disorder under the theoretical models of five schools (including the biological, psychodynamic, cognitive/information processing model, behavioral model, and current etiological conceptualization based on anxiety disorders). Their influence and application, the current commonly used treatment methods and their effectiveness, the current controversies regarding the definition and treatment of chronic PTSD, and recommendations for future research. Overall, based on previous theoretical research and practical treatment, this paper discusses chronic posttraumatic stress disorder from different perspectives and puts forward the existing problems in current research, thus not only offering readers a relatively comprehensive understanding of chronic traumatic stress disorder but also having multiple orientations of summarizing historical research and facing the future.