The aim of this chapter is to focus on the imaging modality of malignant tumors of sinonasal cavities. Sinonasal (SN) malignancies represent 3% of all the malignancies in head and neck regions. Within the SN tract, the malignant tumors are more common as compared to benign tumors. In addition to the primary neoplastic lesions of SN tract, there are many masses which have primary origin in the cranium or skull base or from the maxillary alveolus. This chapter covers the epithelial malignancies, neuroectodermal malignancies, hematolymphoid neoplasms, tumors of soft tissue bone and cartilage, metastasis, and miscellaneous. Squamous cell carcinomas are the most common type of malignancy in SN area (50–80%) with highest incidence in 6th and 7th decades. In SN tract, usually the melanoma is of mucosal variety (unlike cutaneous elsewhere). Melanoma is a rare tumor of SN tract with poor prognosis.