This article reports a young female patient with dengue fever encephalitis. Related clinical data were collected， including clinical symptoms and signs， biochemical markers， imaging findings， and metagenomics testing， and a literature review was performed. The patient was admitted to The First Affiliated Hospital of Army Medical University due to the chief complaint of “pyrexia and headache for 4 days and diarrhea and vomiting for 3 days”. On day 2 after admission， metagenomics testing of cerebrospinal fluid showed dengue virus type 1， with elevated procalcitonin levels， thereby confirming the diagnosis of dengue fever encephalitis. The possibility of dengue fever encephalitis should be considered for patients with pyrexia， headache， diarrhea， vomiting， and elevated procalcitonin levels， and serological tests for dengue fever and dengue fever RNA detection of cerebrospinal fluid should be performed.