Mucocele of the maxillary sinus is a relatively rare location among all the paranasal sinus mucoceles. Maxillary sinus mucoceles usually grow gradually and can erode surrounding structures, which result in associated symptoms. The most common presenting symptoms include dull maxillary facial pain, swelling of the cheek, and nasal obstruction. It is rare to cause orbital and ocular involvement. Here we present a case of a 72-year-old man who sustained swelling around the right cheek and lower eyelid region associated with epiphora and blepharoptosis. Computed tomographic scan of the paranasal sinus revealed a large maxillary mucocele with bony erosion and compression of the right globe. The symptoms of cheek swelling and blepharoptosis resolved immediately after endoscopic marsupialization was performed. The case report demonstrates that maxillary sinus mucoceles may invade the orbit secretly and should be considered in the differential diagnosis in patients presented with eye problems. Early diagnosis and timely surgical intervention are important to reduce inevitable complications.