Otolaryngologists are called upon to evaluate and treat sinonasal masses discovered incidentally on imaging studies. Although common conditions such as sinonasal polyps and mucus retention cysts predominate, it is prudent practice to formulate a differential diagnosis to identify unusual conditions. We present a case of a maxillary sinus mass in a 78-year-old man that was discovered incidentally on brain imaging and subsequently identified on biopsy as an angiomyolipoma (AML). AMLs are benign hamartomatous tumors that rarely occur in extrarenal locations. Only a few cases have been reported in the nasal cavity. We believe our case represents the first reported instance of AML arising within a maxillary sinus. Identification of intratumoral fat within the mass on imaging studies may suggest the diagnosis of AML preoperatively. Close interdisciplinary collaboration among the otorhinolaryngology, radiology, and pathology services is beneficial for patient management. We report this case to raise awareness that AML can arise in this previously unreported location. Moreover, we wish to emphasize that AML should be considered in the differential diagnosis when imaging studies demonstrate a well-defined, heterogeneous, fat-containing solitary mass in the nasal cavity or maxillary sinus.