Abstract: Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a highly malignant hematological tumor derived from the precursor cells of plasmacytoid dendritic cells. BPDCN that primarily originates in the nasal cavity is clinically rare and easily misdiagnosed or missed. At present, there is no standard treatment for BPDCN in China and abroad. This article reported a female patient with BPDCN primarily in the nasal cavity. The regimen of Azacitidine combined with GemOx had a good clinical effect on this patient and significantly controlled the condition and improved the clinical symptoms. This article analyzed and discussed the clinical diagnosis and treatment of this patient, aiming to improve clinicians' understanding of rare BPDCN.