Introduction: Non-Hodgkin lymphoma is a type of neoplasm that affects the lymphoreticular system. Even though bone lesions are rare, it does affect the jaws and, more so, the maxilla than the mandible. Around 40% of NHL originate from the extranodal sites (1). Head and neck NHL is the second most common extranodal site after gastrointestinal tract (2). Presentation of case: we present a case of a 58-year-old male patient with complaints of a continually growing mass in the upper left tooth region of a previously extracted tooth for two weeks. A CBCT scan was done which showed proliferation of a mass into the maxillary sinus along with the presence of an oro-antral fistula and loss of palatal cortical plate. Histopathological evaluation revealed the NHL of the maxillary sinus. Discussion: The second most common malignant pathology of the head and neck area after squamous cell carcinoma; Lymphoma, presents most commonly as a persistent swelling in the oral cavity. Other symptoms may include pain, paresthesia, foul smell, discoloration. Lytic changes may also be seen in the bone upon radiographic examination. Conclusion: NHL of the paranasal sinus is a rare occurrence and tricky to diagnose, hence dentists need to be alert to not take any swelling or ulcerations of the oral cavity at their face value.