The spread of Western medicine to China at the beginning of the 19th century reformed the country's medical service.Medical concepts,techniques,and systems coming from the other side of the world gradually took the place of the local medical traditions and became the mainstream.In this trend,the disease concept of neurasthenia was introduced,the emergence,rising and re-construction of which was entailed in the formulation processes of modern China's knowledge system,from"the eastward dissemination of Western knowledge"to"learning from the Soviet Union".The travel of the concept to the country caused the Chinese people's changing and refining cognition of neuroses and psychoses.When introduced to China,neurasthenia was translated into naoli shuairuo and shenjing shuairuo,and the two terms in translation were observed in newspapers,dictionaries and medical texts.Shenjing shuairuo,first acknowledged as a neurosis,and then a psychosis,was a common disease in the Chinese psychiatric outpatient departments,and its morbidity once exceeded 80%.At the end of the 20th century,the fashionable disease concept silently disappeared in the Chinese discursive domain of mental diseases.In the paper,it is proposed that the introduction to neurasthenia by means of shenjing shuairuo is not simply a case of term translation;nor is the switch from shenjing shuairuo to diseases like melancholia a case of reform of terms.What is behind the switch of terms is the change of concepts,as well as the change of cognition of the travelling knowledge.In the paper,the translation practice of neurasthenia since the 19th century is studied,with its path into China outlined,its reception within the local Chinese context examined,and its translingual practice revisited.