Aims: To increase awareness of the diagnosis HPV-Related Multiphenotypic Sinonasal Carcinoma especially among anatomical pathologists, because histopathology feature of this relatively new entity in WHO head and neck tumor classification is often resembles other diagnoses. Methodology: Case report and literature review. Result: This is a case report of a 51 years old male, with chief complain of a slowly growing mass in the nasal and sinus region for three years, the resected mass was 10.5x4.4x4.8 cm, and initial pathology diagnosis was salivary gland basal cell adenocarcinoma, because of the feature of hyperchromatic basaloid cells that arrange in the palisading pattern at the periphery of the tumor cluster. But further examination revealed that the tumor also has dysplastic surface epithelial, abrupt keratinization, and cartilage metaplasia. Immunohistochemistry showed positivity in ductal marker CK7, Myoepithelial marker SMA and P63, HPV surrogate marker p16, and Positivity in HPV DNA type 82. Based on morphology, histopathology, and HPV DNA testing the final diagnosis was rendered HPV-related multiphenotypic sinonasal carcinoma. The patients was assessed as T4bN2cM1 (costae) after surgery then receive radiotherapy and concurrent chemotherapy. After 3 years of follow up the patient remained free from disease. Conclusion: HPV-related multiphenotypic sinonasal carcinoma is relatively new entity in head and neck tumor, and its morphology is mimicking another tumor such as basal cell adenocarcinoma and adenoid cystic carcinoma, it is very important for pathologist to recognized this entity because of its favorable prognosis despite of high grade appearance. References: Bishop JA, Thompson LDR, et al. Nasal paranasal and skull based tumours. In: WHO Classification of Tumours Editorial Board. Head and neck tumours [Internet]. Lyon (France): International Agency for Research on Cancer; 2023. WHO classification of tumours series, 5th ed.; vol. 9.