Background: Primary progressive aphasia(PPA) is a degenerative disease of nervous system, which is very rare in clinics. Only 3 cases have been reported in our country. There is very little clinical information regarding the characteristics of PPA in linguistics and imageology. Objective: To report the language disorder and the characteristics of imageology of one PPA patient for the clarification of the clinical features of PPA. Design: A case analysis. Setting: Department of Neurology, Beijing Tiantan Hospital; Faculty of Psychology, Beijing Normal University. Paticipant: Male, 56 years old, senior high school graduate, businessman before the onset of the disease. The case visited the department of Neurology, Tiantan Hospital, Beijing due to the complaint of three years of progressive decreasing in language skills, which was then diagnosed with PPA. Methods: Spoken language fluency evaluation in Chinese Aphasia Examination Set of the First Affiliated Hospital of Beijing Medical University was used to evaluate this patient, the type of Aphasia was judged by Western Aphasia Examination Set, and the severity gradation was classified by the Boston Diagnostic Aphasia Examination(BDAE). Memory, intelligence screening and imageology examination were performed as well. Main outcome measures: The fluency of spoken language, the type of aphasia, and the severity of aphasia of the patient were judged, and whether the patient suffered from memory and intelligence disorder were observed as well as the features of imageology. Results: The patient had fluent spoken language, which was evaluated as sensory aphasia(SA) with the aphasia severity of level 4, and had no memory or intelligence disorder. MRI showed atrophy in left frontal lobe and temporal lobe, which was more significant in left side. MRI also showed that left temporal and frontal lobes had low metabolism and low perfusion. Conclusion: PPA is a disease with language disorder as its dominant clinical manifestation, which no other cognitive disorder at its initial stage, and with its main pathological changes in left temporal and frontal lobes.